diff --git a/lib/application.js b/lib/application.js
index be621742dd..c7d484e456 100644
--- a/lib/application.js
+++ b/lib/application.js
@@ -467,8 +467,8 @@ app.render = function(name, options, fn){
   // merge app.locals
   utils.merge(opts, this.locals);
 
-  // merge options.locals
-  if (options.locals) utils.merge(opts, options.locals);
+  // merge options._locals
+  if (options._locals) utils.merge(opts, options._locals);
 
   // merge options
   utils.merge(opts, options);
diff --git a/lib/response.js b/lib/response.js
index f3b2675d05..f3c16717e0 100644
--- a/lib/response.js
+++ b/lib/response.js
@@ -665,7 +665,7 @@ res.render = function(view, options, fn){
   }
 
   // merge res.locals
-  options.locals = self.locals;
+  options._locals = self.locals;
 
   // default callback to respond
   fn = fn || function(err, str){