diff --git a/src/Symfony/Component/Routing/Route.php b/src/Symfony/Component/Routing/Route.php
index de98e1d763..7f20c794c9 100644
--- a/src/Symfony/Component/Routing/Route.php
+++ b/src/Symfony/Component/Routing/Route.php
@@ -137,7 +137,7 @@ class Route implements \Serializable
     public function setPath($pattern)
     {
         if (false !== strpbrk($pattern, '?<')) {
-            $pattern = preg_replace_callback('#\{(\w++)(<.*?>)?(\?[^\}]*+)?\}#', function ($m) {
+            $pattern = preg_replace_callback('#\{(!?\w++)(<.*?>)?(\?[^\}]*+)?\}#', function ($m) {
                 if (isset($m[3][0])) {
                     $this->setDefault($m[1], '?' !== $m[3] ? substr($m[3], 1) : null);
                 }
diff --git a/src/Symfony/Component/Routing/Tests/RouteTest.php b/src/Symfony/Component/Routing/Tests/RouteTest.php
index 4c767f9d95..c02af42ce7 100644
--- a/src/Symfony/Component/Routing/Tests/RouteTest.php
+++ b/src/Symfony/Component/Routing/Tests/RouteTest.php
@@ -208,6 +208,7 @@ class RouteTest extends TestCase
         $this->assertEquals((new Route('/foo/{bar}'))->setDefault('bar', null), new Route('/foo/{bar?}'));
         $this->assertEquals((new Route('/foo/{bar}'))->setDefault('bar', 'baz'), new Route('/foo/{bar?baz}'));
         $this->assertEquals((new Route('/foo/{bar}'))->setDefault('bar', 'baz<buz>'), new Route('/foo/{bar?baz<buz>}'));
+        $this->assertEquals((new Route('/foo/{!bar}'))->setDefault('!bar', 'baz<buz>'), new Route('/foo/{!bar?baz<buz>}'));
         $this->assertEquals((new Route('/foo/{bar}'))->setDefault('bar', 'baz'), new Route('/foo/{bar?}', ['bar' => 'baz']));
 
         $this->assertEquals((new Route('/foo/{bar}'))->setRequirement('bar', '.*'), new Route('/foo/{bar<.*>}'));