diff --git a/src/pixi/core/Rectangle.js b/src/pixi/core/Rectangle.js
index 6ac1884..0b26270 100644
--- a/src/pixi/core/Rectangle.js
+++ b/src/pixi/core/Rectangle.js
@@ -57,7 +57,7 @@
  * @param y {Number} The Y coord of the point to test
  * @return if the x/y coords are within this polygon
  */
-PIXI.Rectangle.contains = function(x, y)
+PIXI.Rectangle.prototype.contains = function(x, y)
 {
     if(this.width <= 0 || this.height <= 0)
         return false;