diff --git a/src/tiledimage.js b/src/tiledimage.js
index 347a5b3e..cc05cb57 100644
--- a/src/tiledimage.js
+++ b/src/tiledimage.js
@@ -326,6 +326,10 @@ $.extend($.TiledImage.prototype, $.EventSource.prototype, /** @lends OpenSeadrag
      */
     destroy: function() {
         this.reset();
+
+        if (this.source.destroy) {
+            this.source.destroy();
+        }
     },
 
     /**
diff --git a/src/viewer.js b/src/viewer.js
index 93217150..20e06186 100644
--- a/src/viewer.js
+++ b/src/viewer.js
@@ -742,11 +742,6 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
             return;
         }
 
-        //TODO: implement destroy and _freeupCanvasMemory method for all child classes of TileSource, then remove if statement wrap below.
-        if (this.source.destroy) {
-            this.source.destroy();
-        }
-
         this.close();
 
         this.clearOverlays();