diff --git a/core/Tracker.php b/core/Tracker.php
index d9d477a0ded8595824ed5acb6a1630cda10102dd..4e0e97fb096b5d3bb4fca48645cb1edaca57a012 100644
--- a/core/Tracker.php
+++ b/core/Tracker.php
@@ -177,6 +177,7 @@ class Piwik_Tracker
 		if(isset(self::$db))
 		{
 			self::$db->disconnect();
+			self::$db = null;
 		}
 	}