diff --git a/src/compiler/transformers/esnext.ts b/src/compiler/transformers/esnext.ts
index 3aa5be551a6..29cdbad5e7f 100644
--- a/src/compiler/transformers/esnext.ts
+++ b/src/compiler/transformers/esnext.ts
@@ -126,16 +126,19 @@ namespace ts {
         function visitYieldExpression(node: YieldExpression) {
             if (enclosingFunctionFlags & FunctionFlags.Async && enclosingFunctionFlags & FunctionFlags.Generator) {
                 const expression = visitNode(node.expression, visitor, isExpression);
-                return updateYield(
+                const delegator = node.asteriskToken && updateYield(
                     node,
                     node.asteriskToken,
-                    node.asteriskToken
-                        ? createAsyncDelegatorHelper(context, expression, expression)
-                        : createArrayLiteral(
-                            expression
-                            ? [createLiteral("yield"), expression]
-                            : [createLiteral("yield")]
-                        )
+                    createAsyncDelegatorHelper(context, expression, expression)
+                );
+                return updateYield(
+                    node,
+                    /*asteriskToken*/ undefined,
+                    createArrayLiteral(
+                        delegator ? [createLiteral("await"), delegator] :
+                        expression ? [createLiteral("yield"), expression] :
+                        [createLiteral("yield")]
+                    )
                 );
             }
             return visitEachChild(node, visitor, context);
@@ -922,9 +925,9 @@ namespace ts {
         scoped: false,
         text: `
             var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-                var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-                return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-                function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+                var i, f;
+                return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+                function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
             };
         `
     };
diff --git a/tests/baselines/reference/emitter.asyncGenerators.classMethods.es2015.js b/tests/baselines/reference/emitter.asyncGenerators.classMethods.es2015.js
index fbefef62d05..58a4306c113 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.classMethods.es2015.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.classMethods.es2015.js
@@ -124,9 +124,9 @@ class C3 {
 }
 //// [C4.js]
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -149,7 +149,7 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
 class C4 {
     f() {
         return __asyncGenerator(this, arguments, function* f_1() {
-            const x = yield* __asyncDelegator([1]);
+            const x = yield ["await", yield* __asyncDelegator([1])];
         });
     }
 }
@@ -168,9 +168,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -180,7 +180,7 @@ var __asyncValues = (this && this.__asyncIterator) || function (o) {
 class C5 {
     f() {
         return __asyncGenerator(this, arguments, function* f_1() {
-            const x = yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })());
+            const x = yield ["await", yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })())];
         });
     }
 }
diff --git a/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js b/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js
index 0c58c4735a0..cb4418936be 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js
@@ -260,9 +260,9 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -297,12 +297,15 @@ var C4 = (function () {
     }
     C4.prototype.f = function () {
         return __asyncGenerator(this, arguments, function f_1() {
-            var x;
-            return __generator(this, function (_a) {
-                switch (_a.label) {
-                    case 0: return [5 /*yield**/, __values(__asyncDelegator([1]))];
-                    case 1:
-                        x = _a.sent();
+            var x, _a;
+            return __generator(this, function (_b) {
+                switch (_b.label) {
+                    case 0:
+                        _a = ["await"];
+                        return [5 /*yield**/, __values(__asyncDelegator([1]))];
+                    case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                    case 2:
+                        x = _b.sent();
                         return [2 /*return*/];
                 }
             });
@@ -352,9 +355,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -376,19 +379,22 @@ var C5 = (function () {
     }
     C5.prototype.f = function () {
         return __asyncGenerator(this, arguments, function f_1() {
-            var x;
-            return __generator(this, function (_a) {
-                switch (_a.label) {
-                    case 0: return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
-                            switch (_a.label) {
-                                case 0: return [4 /*yield*/, ["yield", 1]];
-                                case 1:
-                                    _a.sent();
-                                    return [2 /*return*/];
-                            }
-                        }); }); })()))];
-                    case 1:
-                        x = _a.sent();
+            var x, _a;
+            return __generator(this, function (_b) {
+                switch (_b.label) {
+                    case 0:
+                        _a = ["await"];
+                        return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
+                                switch (_a.label) {
+                                    case 0: return [4 /*yield*/, ["yield", 1]];
+                                    case 1:
+                                        _a.sent();
+                                        return [2 /*return*/];
+                                }
+                            }); }); })()))];
+                    case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                    case 2:
+                        x = _b.sent();
                         return [2 /*return*/];
                 }
             });
diff --git a/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es2015.js b/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es2015.js
index daf188ba33f..a3a6baf319a 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es2015.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es2015.js
@@ -87,9 +87,9 @@ function f3() {
 }
 //// [F4.js]
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -111,7 +111,7 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
 };
 function f4() {
     return __asyncGenerator(this, arguments, function* f4_1() {
-        const x = yield* __asyncDelegator([1]);
+        const x = yield ["await", yield* __asyncDelegator([1])];
     });
 }
 //// [F5.js]
@@ -129,9 +129,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -140,7 +140,7 @@ var __asyncValues = (this && this.__asyncIterator) || function (o) {
 };
 function f5() {
     return __asyncGenerator(this, arguments, function* f5_1() {
-        const x = yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })());
+        const x = yield ["await", yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })())];
     });
 }
 //// [F6.js]
diff --git a/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js b/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js
index 71f685e24dd..1e75fb61c2f 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js
@@ -214,9 +214,9 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -248,12 +248,15 @@ var __values = (this && this.__values) || function (o) {
 };
 function f4() {
     return __asyncGenerator(this, arguments, function f4_1() {
-        var x;
-        return __generator(this, function (_a) {
-            switch (_a.label) {
-                case 0: return [5 /*yield**/, __values(__asyncDelegator([1]))];
-                case 1:
-                    x = _a.sent();
+        var x, _a;
+        return __generator(this, function (_b) {
+            switch (_b.label) {
+                case 0:
+                    _a = ["await"];
+                    return [5 /*yield**/, __values(__asyncDelegator([1]))];
+                case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                case 2:
+                    x = _b.sent();
                     return [2 /*return*/];
             }
         });
@@ -301,9 +304,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -322,19 +325,22 @@ var __values = (this && this.__values) || function (o) {
 };
 function f5() {
     return __asyncGenerator(this, arguments, function f5_1() {
-        var x;
-        return __generator(this, function (_a) {
-            switch (_a.label) {
-                case 0: return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
-                        switch (_a.label) {
-                            case 0: return [4 /*yield*/, ["yield", 1]];
-                            case 1:
-                                _a.sent();
-                                return [2 /*return*/];
-                        }
-                    }); }); })()))];
-                case 1:
-                    x = _a.sent();
+        var x, _a;
+        return __generator(this, function (_b) {
+            switch (_b.label) {
+                case 0:
+                    _a = ["await"];
+                    return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
+                            switch (_a.label) {
+                                case 0: return [4 /*yield*/, ["yield", 1]];
+                                case 1:
+                                    _a.sent();
+                                    return [2 /*return*/];
+                            }
+                        }); }); })()))];
+                case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                case 2:
+                    x = _b.sent();
                     return [2 /*return*/];
             }
         });
diff --git a/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es2015.js b/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es2015.js
index bb2562db780..475445b2f0a 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es2015.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es2015.js
@@ -87,9 +87,9 @@ const f3 = function () {
 };
 //// [F4.js]
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -111,7 +111,7 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
 };
 const f4 = function () {
     return __asyncGenerator(this, arguments, function* () {
-        const x = yield* __asyncDelegator([1]);
+        const x = yield ["await", yield* __asyncDelegator([1])];
     });
 };
 //// [F5.js]
@@ -129,9 +129,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -140,7 +140,7 @@ var __asyncValues = (this && this.__asyncIterator) || function (o) {
 };
 const f5 = function () {
     return __asyncGenerator(this, arguments, function* () {
-        const x = yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })());
+        const x = yield ["await", yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })())];
     });
 };
 //// [F6.js]
diff --git a/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js b/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js
index 1863548c141..bb94d82d7b6 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js
@@ -214,9 +214,9 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -248,12 +248,15 @@ var __values = (this && this.__values) || function (o) {
 };
 var f4 = function () {
     return __asyncGenerator(this, arguments, function () {
-        var x;
-        return __generator(this, function (_a) {
-            switch (_a.label) {
-                case 0: return [5 /*yield**/, __values(__asyncDelegator([1]))];
-                case 1:
-                    x = _a.sent();
+        var x, _a;
+        return __generator(this, function (_b) {
+            switch (_b.label) {
+                case 0:
+                    _a = ["await"];
+                    return [5 /*yield**/, __values(__asyncDelegator([1]))];
+                case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                case 2:
+                    x = _b.sent();
                     return [2 /*return*/];
             }
         });
@@ -301,9 +304,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -322,19 +325,22 @@ var __values = (this && this.__values) || function (o) {
 };
 var f5 = function () {
     return __asyncGenerator(this, arguments, function () {
-        var x;
-        return __generator(this, function (_a) {
-            switch (_a.label) {
-                case 0: return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
-                        switch (_a.label) {
-                            case 0: return [4 /*yield*/, ["yield", 1]];
-                            case 1:
-                                _a.sent();
-                                return [2 /*return*/];
-                        }
-                    }); }); })()))];
-                case 1:
-                    x = _a.sent();
+        var x, _a;
+        return __generator(this, function (_b) {
+            switch (_b.label) {
+                case 0:
+                    _a = ["await"];
+                    return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
+                            switch (_a.label) {
+                                case 0: return [4 /*yield*/, ["yield", 1]];
+                                case 1:
+                                    _a.sent();
+                                    return [2 /*return*/];
+                            }
+                        }); }); })()))];
+                case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                case 2:
+                    x = _b.sent();
                     return [2 /*return*/];
             }
         });
diff --git a/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es2015.js b/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es2015.js
index 5a200349c02..eedbfaf5998 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es2015.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es2015.js
@@ -107,9 +107,9 @@ const o3 = {
 };
 //// [O4.js]
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -132,7 +132,7 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
 const o4 = {
     f() {
         return __asyncGenerator(this, arguments, function* f_1() {
-            const x = yield* __asyncDelegator([1]);
+            const x = yield ["await", yield* __asyncDelegator([1])];
         });
     }
 };
@@ -151,9 +151,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -163,7 +163,7 @@ var __asyncValues = (this && this.__asyncIterator) || function (o) {
 const o5 = {
     f() {
         return __asyncGenerator(this, arguments, function* f_1() {
-            const x = yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })());
+            const x = yield ["await", yield* __asyncDelegator((function () { return __asyncGenerator(this, arguments, function* () { yield ["yield", 1]; }); })())];
         });
     }
 };
diff --git a/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js b/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js
index abb3f0ca074..c108d49a26f 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js
@@ -234,9 +234,9 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -269,12 +269,15 @@ var __values = (this && this.__values) || function (o) {
 var o4 = {
     f: function () {
         return __asyncGenerator(this, arguments, function f_1() {
-            var x;
-            return __generator(this, function (_a) {
-                switch (_a.label) {
-                    case 0: return [5 /*yield**/, __values(__asyncDelegator([1]))];
-                    case 1:
-                        x = _a.sent();
+            var x, _a;
+            return __generator(this, function (_b) {
+                switch (_b.label) {
+                    case 0:
+                        _a = ["await"];
+                        return [5 /*yield**/, __values(__asyncDelegator([1]))];
+                    case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                    case 2:
+                        x = _b.sent();
                         return [2 /*return*/];
                 }
             });
@@ -323,9 +326,9 @@ var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _ar
     function settle(f, v) { c = void 0, f(v), next(); }
 };
 var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {
-    var i = { next: verb("next"), "throw": verb("throw", function (e) { throw e; }), "return": verb("return", function (v) { return { value: v, done: true }; }) }, p;
-    return o = __asyncValues(o), i[Symbol.iterator] = function () { return this; }, i;
-    function verb(n, f) { return function (v) { return v = p && n === "throw" ? f(v) : p && v.done ? v : { value: p ? ["yield", v.value] : ["await", (o[n] || f).call(o, v)], done: false }, p = !p, v; }; }
+    var i, f;
+    return o = __asyncValues(o), i = { next: verb("next"), "throw": verb("throw"), "return": verb("return") }, i[Symbol.iterator] = function () { return this; }, i;
+    function verb(n) { return o[n] && function (b) { return (f = !f) ? { value: ["await", new Promise(function(r) { r(o[n](b)); })], done: n === "return" } : b.done ? b : { value: ["yield", b.value], done: false }; }; }
 };
 var __asyncValues = (this && this.__asyncIterator) || function (o) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
@@ -345,19 +348,22 @@ var __values = (this && this.__values) || function (o) {
 var o5 = {
     f: function () {
         return __asyncGenerator(this, arguments, function f_1() {
-            var x;
-            return __generator(this, function (_a) {
-                switch (_a.label) {
-                    case 0: return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
-                            switch (_a.label) {
-                                case 0: return [4 /*yield*/, ["yield", 1]];
-                                case 1:
-                                    _a.sent();
-                                    return [2 /*return*/];
-                            }
-                        }); }); })()))];
-                    case 1:
-                        x = _a.sent();
+            var x, _a;
+            return __generator(this, function (_b) {
+                switch (_b.label) {
+                    case 0:
+                        _a = ["await"];
+                        return [5 /*yield**/, __values(__asyncDelegator((function () { return __asyncGenerator(this, arguments, function () { return __generator(this, function (_a) {
+                                switch (_a.label) {
+                                    case 0: return [4 /*yield*/, ["yield", 1]];
+                                    case 1:
+                                        _a.sent();
+                                        return [2 /*return*/];
+                                }
+                            }); }); })()))];
+                    case 1: return [4 /*yield*/, _a.concat([_b.sent()])];
+                    case 2:
+                        x = _b.sent();
                         return [2 /*return*/];
                 }
             });