diff --git a/wp-includes/query.php b/wp-includes/query.php
index 5f03e5e452..fd7b686953 100644
--- a/wp-includes/query.php
+++ b/wp-includes/query.php
@@ -998,14 +998,7 @@ class WP_Query {
 				}
 			} else {
 				$q['tag'] = sanitize_term_field('slug', $q['tag'], 0, 'post_tag', 'db');
-				$reqtag = is_term( $q['tag'], 'post_tag' );
-				if ( !empty($reqtag) )
-					$reqtag = $reqtag['term_id'];
-				else
-					$reqtag = 0;
-
-				$q['tag_id'] = $reqtag;
-				$q['tag__in'][] = $reqtag;
+				$q['tag_slug__in'][] = $q['tag'];
 			}
 		}