diff --git a/closure/goog/timer/timer.js b/closure/goog/timer/timer.js
index <HASH>..<HASH> 100644
--- a/closure/goog/timer/timer.js
+++ b/closure/goog/timer/timer.js
@@ -165,6 +165,10 @@ goog.Timer.prototype.tick_ = function() {
       return;
     }
 
+    // Prevents setInterval from registering a duplicate timeout when called
+    // in the timer event handler.
+    this.timer_ = null;
+
     this.dispatchTick();
     // The timer could be stopped in the timer event handler.
     if (this.enabled) {
Prevent unwanted duplicate timeouts from being registered when
calling setInterval on an enabled timer from within a timer event
handler.
-------------
Created by MOE: <URL>