diff --git a/src/compiler/transformers/ts.ts b/src/compiler/transformers/ts.ts
index 7eb10f7342e..5061d7f089e 100644
--- a/src/compiler/transformers/ts.ts
+++ b/src/compiler/transformers/ts.ts
@@ -910,7 +910,7 @@ namespace ts {
                     createAssignment(
                         createPropertyAccess(
                             createThis(),
-                            getSynthesizedClone(<Identifier>node.name),
+                            getMutableClone(<Identifier>node.name),
                             /*location*/ node.name
                         ),
                         getUniqueClone(<Identifier>node.name)
diff --git a/tests/baselines/reference/escapedIdentifiers.js b/tests/baselines/reference/escapedIdentifiers.js
index c1b5fe8ae09..b326dbf1ecc 100644
--- a/tests/baselines/reference/escapedIdentifiers.js
+++ b/tests/baselines/reference/escapedIdentifiers.js
@@ -143,7 +143,7 @@ var moduleType1;
 (function (moduleType1) {
 })(moduleType1 || (moduleType1 = {}));
 var moduleType\u0032;
-(function (moduleType2) {
+(function (moduleType\u0032) {
 })(moduleType\u0032 || (moduleType\u0032 = {}));
 moduleType1.baz1 = 3;
 moduleType\u0031.baz1 = 3;