diff --git a/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php
index b50386cb96..f9730b1485 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php
@@ -164,6 +164,16 @@ class DumpDataCollector extends DataCollector implements DataDumperInterface
         }
     }
 
+    public function reset()
+    {
+        $this->stopwatch->reset();
+        $this->data = array();
+        $this->dataCount = 0;
+        $this->isCollected = false;
+        $this->clonesCount = 0;
+        $this->clonesIndex = 0;
+    }
+
     public function serialize()
     {
         if ($this->clonesCount !== $this->clonesIndex) {
diff --git a/src/Symfony/Component/HttpKernel/DataCollector/TimeDataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/TimeDataCollector.php
index 6588304935..e489d77598 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/TimeDataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/TimeDataCollector.php
@@ -14,6 +14,7 @@ namespace Symfony\Component\HttpKernel\DataCollector;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpKernel\KernelInterface;
+use Symfony\Component\Stopwatch\Stopwatch;
 
 /**
  * TimeDataCollector.
@@ -25,7 +26,7 @@ class TimeDataCollector extends DataCollector implements LateDataCollectorInterf
     protected $kernel;
     protected $stopwatch;
 
-    public function __construct(KernelInterface $kernel = null, $stopwatch = null)
+    public function __construct(KernelInterface $kernel = null, Stopwatch $stopwatch = null)
     {
         $this->kernel = $kernel;
         $this->stopwatch = $stopwatch;
@@ -55,6 +56,10 @@ class TimeDataCollector extends DataCollector implements LateDataCollectorInterf
     public function reset()
     {
         $this->data = array();
+
+        if (null !== $this->stopwatch) {
+            $this->stopwatch->reset();
+        }
     }
 
     /**