diff --git a/plugins/system/sef/sef.php b/plugins/system/sef/sef.php
index b9b8b534c59b6..5684df8e282f2 100644
--- a/plugins/system/sef/sef.php
+++ b/plugins/system/sef/sef.php
@@ -123,7 +123,7 @@ public function onAfterRender()
 		{
 			if (strpos($buffer, $attribute) !== false)
 			{
-				$regex  = '#\s+' . $attribute . '"(?!/|' . $protocols . '|\#|\')([^"]*)"#m';
+				$regex  = '#\s' . $attribute . '"(?!/|' . $protocols . '|\#|\')([^"]*)"#m';
 				$buffer = preg_replace($regex, ' ' . $attribute . '"' . $base . '$1"', $buffer);
 				$this->checkBuffer($buffer);
 			}