diff --git a/wp-admin/nav-menus.php b/wp-admin/nav-menus.php
index e22539e08a..847fc07d9e 100644
--- a/wp-admin/nav-menus.php
+++ b/wp-admin/nav-menus.php
@@ -290,9 +290,6 @@ switch ( $action ) {
 				if ( is_wp_error( $_nav_menu_selected_id ) ) {
 					$messages[] = '<div id="message" class="error"><p>' . $_nav_menu_selected_id->get_error_message() . '</p></div>';
 				} else {
-					if ( ( $_menu_locations = get_registered_nav_menus() ) && 1 == count( wp_get_nav_menus() ) )
-						set_theme_mod( 'nav_menu_locations', array( key( $_menu_locations ) => $_nav_menu_selected_id ) );
-					unset( $_menu_locations );
 					$_menu_object = wp_get_nav_menu_object( $_nav_menu_selected_id );
 					$nav_menu_selected_id = $_nav_menu_selected_id;
 					$nav_menu_selected_title = $_menu_object->name;