diff --git a/src/ol/renderer/layer.js b/src/ol/renderer/layer.js
index a5745e1377..413e3f25bc 100644
--- a/src/ol/renderer/layer.js
+++ b/src/ol/renderer/layer.js
@@ -152,8 +152,10 @@ ol.renderer.Layer.prototype.scheduleExpireCache = function(frameState, tileSourc
      */
     var postRenderFunction = function(tileSource, map, frameState) {
       var tileSourceKey = ol.getUid(tileSource).toString();
-      tileSource.expireCache(frameState.viewState.projection,
-          frameState.usedTiles[tileSourceKey]);
+      if (tileSourceKey in frameState.usedTiles) {
+        tileSource.expireCache(frameState.viewState.projection,
+            frameState.usedTiles[tileSourceKey]);
+      }
     }.bind(null, tileSource);
 
     frameState.postRenderFunctions.push(