diff --git a/src/Illuminate/Routing/RouteRegistrar.php b/src/Illuminate/Routing/RouteRegistrar.php
index 315314df0a48..679b10c28080 100644
--- a/src/Illuminate/Routing/RouteRegistrar.php
+++ b/src/Illuminate/Routing/RouteRegistrar.php
@@ -183,6 +183,10 @@ protected function compileAction($action)
         if (is_array($action) &&
             is_callable($action) &&
             ! Arr::isAssoc($action)) {
+            if (strncmp($action[0], '\\', 1)) {
+                $action[0] = '\\'.$action[0];
+            }
+
             $action = [
                 'uses' => $action[0].'@'.$action[1],
                 'controller' => $action[0].'@'.$action[1],
diff --git a/tests/Routing/RouteRegistrarTest.php b/tests/Routing/RouteRegistrarTest.php
index a6bc297aa40d..2f97be3e03e5 100644
--- a/tests/Routing/RouteRegistrarTest.php
+++ b/tests/Routing/RouteRegistrarTest.php
@@ -149,6 +149,25 @@ public function testCanRegisterRouteWithControllerActionArray()
         $this->seeMiddleware('controller-middleware');
     }
 
+    public function testCanRegisterNamespacedGroupRouteWithControllerActionArray()
+    {
+        $this->router->group(['namespace' => 'WhatEver'], function () {
+            $this->router->middleware('controller-middleware')
+                ->get('users', [RouteRegistrarControllerStub::class, 'index']);
+        });
+
+        $this->seeResponse('controller', Request::create('users', 'GET'));
+        $this->seeMiddleware('controller-middleware');
+
+        $this->router->group(['namespace' => 'WhatEver'], function () {
+            $this->router->middleware('controller-middleware')
+                ->get('users', ['\\'.RouteRegistrarControllerStub::class, 'index']);
+        });
+
+        $this->seeResponse('controller', Request::create('users', 'GET'));
+        $this->seeMiddleware('controller-middleware');
+    }
+
     public function testCanRegisterRouteWithArrayAndControllerAction()
     {
         $this->router->middleware('controller-middleware')->put('users', [