diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 6767bdf..8367ea0 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -2298,14 +2298,16 @@ function system_update_8060() {
  * Rename the router table 'route_set' field to 'provider'.
  */
 function system_update_8061() {
-  $field = array(
-    'description' => 'The provider grouping to which a route belongs.',
-    'type' => 'varchar',
-    'length' => 255,
-    'not null' => TRUE,
-    'default' => '',
-  );
-  db_change_field('router', 'route_set', 'provider', $field);
+  if (db_field_exists('router', 'route_set')) {
+    $field = array(
+      'description' => 'The provider grouping to which a route belongs.',
+      'type' => 'varchar',
+      'length' => 255,
+      'not null' => TRUE,
+      'default' => '',
+    );
+    db_change_field('router', 'route_set', 'provider', $field);
+  }
 }
 
 /**