diff --git a/wp-includes/query.php b/wp-includes/query.php
index c0816bb3f..21ac86347 100644
--- a/wp-includes/query.php
+++ b/wp-includes/query.php
@@ -923,7 +923,8 @@ class WP_Query {
 					$reqpage = 0;
 			}
 
-			if  ( ('page' != get_option('show_on_front') ) || ( $reqpage != get_option('page_for_posts') ) ) {
+			$page_for_posts = get_option('page_for_posts');
+			if  ( ('page' != get_option('show_on_front') ) ||  empty($page_for_posts) || ( $reqpage != $page_for_posts ) ) {
 				$q['pagename'] = str_replace('%2F', '/', urlencode(urldecode($q['pagename'])));
 				$page_paths = '/' . trim($q['pagename'], '/');
 				$q['pagename'] = sanitize_title(basename($page_paths));