diff --git a/worldedit-core/src/main/java/com/fastasyncworldedit/core/command/tool/brush/BlendBall.java b/worldedit-core/src/main/java/com/fastasyncworldedit/core/command/tool/brush/BlendBall.java
index 47ccb3260..902e48a9b 100644
--- a/worldedit-core/src/main/java/com/fastasyncworldedit/core/command/tool/brush/BlendBall.java
+++ b/worldedit-core/src/main/java/com/fastasyncworldedit/core/command/tool/brush/BlendBall.java
@@ -136,7 +136,7 @@ public class BlendBall implements Brush {
     }
 
     private boolean maskFails(EditSession editSession, MutableBlockVector3 mutable) {
-        return mask == null || !mask.test(editSession, mutable);
+        return mask != null && !mask.test(editSession, mutable);
     }
 
 }