diff --git a/modules/system/system.module b/modules/system/system.module
index 0c0a49b704b..9036152e59e 100644
--- a/modules/system/system.module
+++ b/modules/system/system.module
@@ -2128,7 +2128,7 @@ function theme_admin_page($blocks) {
     }
   }
 
-  $output = '<div class="admin">';
+  $output = '<div class="admin clear-block">';
   $output .= '<div class="compact-link">';
   if (system_admin_compact_mode()) {
     $output .= l(t('Show descriptions'), 'admin/compact/off', array('title' => t('Produce a less compact layout that includes descriptions.')));