diff --git a/src/ol/control/control.js b/src/ol/control/control.js
index 7760d6e3f2..e63ba7671a 100644
--- a/src/ol/control/control.js
+++ b/src/ol/control/control.js
@@ -76,7 +76,7 @@ ol.control.Control.prototype.getMap = function() {
  * UI.
  * @param {ol.MapEvent} mapEvent Map event.
  */
-ol.control.Control.prototype.handleMapPostrender = goog.nullFunction;
+ol.control.Control.prototype.handleMapPostrender = function(mapEvent) {};
 
 
 /**
@@ -98,7 +98,8 @@ ol.control.Control.prototype.setMap = function(map) {
     var target = goog.isDef(this.target_) ?
         this.target_ : map.getOverlayContainer();
     goog.dom.appendChild(target, this.element);
-    if (this.handleMapPostrender !== goog.nullFunction) {
+    if (this.handleMapPostrender !==
+        ol.control.Control.prototype.handleMapPostrender) {
       this.listenerKeys.push(goog.events.listen(map,
           ol.MapEventType.POSTRENDER, this.handleMapPostrender, false, this));
     }