Index: wp-includes/class-wp-query.php
===================================================================
--- wp-includes/class-wp-query.php	(revision 48506)
+++ wp-includes/class-wp-query.php	(working copy)
@@ -2365,7 +2365,7 @@
 		// Order search results by relevance only when another "orderby" is not specified in the query.
 		if ( ! empty( $q['s'] ) ) {
 			$search_orderby = '';
-			if ( ! empty( $q['search_orderby_title'] ) && ( empty( $q['orderby'] ) && ! $this->is_feed ) || ( isset( $q['orderby'] ) && 'relevance' === $q['orderby'] ) ) {
+			if ( ! empty( $q['search_orderby_title'] ) && ( ( empty( $q['orderby'] ) && ! $this->is_feed ) || ( isset( $q['orderby'] ) && 'relevance' === $q['orderby'] ) ) ) {
 				$search_orderby = $this->parse_search_order( $q );
 			}