diff --git a/js/ui/boxpointer.js b/js/ui/boxpointer.js
index 82d28cd83..c7a8f92d0 100644
--- a/js/ui/boxpointer.js
+++ b/js/ui/boxpointer.js
@@ -556,7 +556,7 @@ var BoxPointer = GObject.registerClass({
                 arrowOrigin = y1;
             } else if (arrowOrigin >= (y2 - (borderRadius + halfBase))) {
                 if (arrowOrigin < y2)
-                    resX -= y2 - arrowOrigin;
+                    resY -= y2 - arrowOrigin;
                 arrowOrigin = y2;
             }
             break;