diff --git a/wp-includes/template-functions-links.php b/wp-includes/template-functions-links.php
index c5094b12dd..e64882cf84 100644
--- a/wp-includes/template-functions-links.php
+++ b/wp-includes/template-functions-links.php
@@ -244,10 +244,10 @@ function edit_comment_link($link = 'Edit This', $before = '', $after = '') {
 
 function previous_post($format='%', $previous='previous post: ', $title='yes', $in_same_cat='no', $limitprev=1, $excluded_categories='') {
     global $id, $post, $wpdb;
-    global $p, $posts, $posts_per_page, $s, $single;
+    global $posts, $posts_per_page, $s;
     global $querystring_start, $querystring_equal, $querystring_separator;
 
-    if(($p) || ($posts_per_page == 1) || 1 == $single) {
+    if(($posts_per_page == 1) || is_single()) {
 
         $current_post_date = $post->post_date;
         $current_category = $post->post_category;
@@ -281,8 +281,8 @@ function previous_post($format='%', $previous='previous post: ', $title='yes', $
 }
 
 function next_post($format='%', $next='next post: ', $title='yes', $in_same_cat='no', $limitnext=1, $excluded_categories='') {
-    global $posts_per_page, $post, $wpdb, $single;
-    if(1 == $posts_per_page || 1 == $single) {
+    global $posts_per_page, $post, $wpdb;
+    if(1 == $posts_per_page || is_single()) {
 
         $current_post_date = $post->post_date;
         $current_category = $post->post_category;