diff --git a/lib/6to5/transformation/modules/common.js b/lib/6to5/transformation/modules/common.js
index 950b35790e..73653c8d04 100644
--- a/lib/6to5/transformation/modules/common.js
+++ b/lib/6to5/transformation/modules/common.js
@@ -27,7 +27,9 @@ CommonJSFormatter.prototype.importSpecifier = function (specifier, node, nodes)
 
   // import foo from "foo";
   if (t.isSpecifierDefault(specifier)) {
-    var ref = util.template("require", {MODULE_NAME: node.source});
+    var ref = util.template("require", {
+      MODULE_NAME: node.source
+    });
     if (!_.contains(this.file.dynamicImports, node)) {
       ref = t.callExpression(this.file.addHelper("interop-require"), [ref]);
     }
diff --git a/lib/6to5/transformation/transformers/optional-self-contained.js b/lib/6to5/transformation/transformers/optional-self-contained.js
index 0ab0cdbd3a..0fd9eac9f3 100644
--- a/lib/6to5/transformation/transformers/optional-self-contained.js
+++ b/lib/6to5/transformation/transformers/optional-self-contained.js
@@ -70,9 +70,8 @@ exports.ast = {
   }
 };
 
-exports.MemberExpression = function (node, parent, scope, context, file) {
-  var obj = node.object;
-  var prop = node.property;
-  if (!t.isReferenced(node, parent) || !t.isReferenced(obj, node)) return;
-  if (obj.name === "regeneratorRuntime") return t.memberExpression(file._regeneratorId, prop);
+exports.Identifier = function (node, parent, scope, context, file) {
+  if (node.name === "regeneratorRuntime" && t.isReferenced(node, parent)) {
+    node.name = file._regeneratorId;
+  }
 };