diff --git a/mod/assignment/lib.php b/mod/assignment/lib.php
index 4b2daf02ec1..d2544589ff4 100644
--- a/mod/assignment/lib.php
+++ b/mod/assignment/lib.php
@@ -1999,8 +1999,14 @@ class assignment_base {
      * @return array
      */
     function get_graders($user) {
+        global $DB;
+
         //potential graders
-        $potgraders = get_users_by_capability($this->context, 'mod/assignment:grade', '', '', '', '', '', '', false, false);
+        list($enrolledsql, $params) = get_enrolled_sql($this->context, 'mod/assignment:grade', 0, true);
+        $sql = "SELECT u.*
+                  FROM {user} u
+                  JOIN ($enrolledsql) je ON je.id = u.id";
+        $potgraders = $DB->get_records_sql($sql, $params);
 
         $graders = array();
         if (groups_get_activity_groupmode($this->cm) == SEPARATEGROUPS) {   // Separate groups are being used