diff --git a/src/core/graphics/Graphics.js b/src/core/graphics/Graphics.js
index 96ffd84..aa4acab 100644
--- a/src/core/graphics/Graphics.js
+++ b/src/core/graphics/Graphics.js
@@ -656,7 +656,7 @@
 
     var closed = true;
     
-    if (points instanceof math.Polygon)
+    if (points instanceof PIXI.Polygon)
     {
         closed = points.closed;
         points = points.points;