diff --git a/test/timers/test-timers-reliability.js b/test/timers/test-timers-reliability.js
index 76aa6ea31afe4d..11c2ced15bf782 100644
--- a/test/timers/test-timers-reliability.js
+++ b/test/timers/test-timers-reliability.js
@@ -32,7 +32,7 @@ var intervalFired = false;
  */
 
 var monoTimer = new Timer();
-monoTimer.ontimeout = function() {
+monoTimer[Timer.kOnTimeout] = function() {
     /*
      * Make sure that setTimeout's and setInterval's callbacks have
      * already fired, otherwise it means that they are vulnerable to