diff --git a/wp-includes/author-template.php b/wp-includes/author-template.php
index 48db8f925..ab2737c56 100644
--- a/wp-includes/author-template.php
+++ b/wp-includes/author-template.php
@@ -135,7 +135,7 @@ function the_author_meta($field = '', $user_id = false) {
  */
 function get_the_author_link() {
 	if ( get_the_author_meta('url') ) {
-		return '<a href="' . get_the_author_meta('url') . '" title="' . esc_attr( sprintf(__("Visit %s&#8217;s website"), get_the_author()) ) . '" rel="external">' . get_the_author() . '</a>';
+		return '<a href="' . get_the_author_meta('url') . '" title="' . esc_attr( sprintf(__("Visit %s&#8217;s website"), get_the_author()) ) . '" rel="author external">' . get_the_author() . '</a>';
 	} else {
 		return get_the_author();
 	}