diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/ExistingBlockMask.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/ExistingBlockMask.java
index be62c2eae7..6e1da09bce 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/ExistingBlockMask.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/ExistingBlockMask.java
@@ -46,7 +46,7 @@ public boolean test(BlockVector3 vector) {
 
     @Override
     public boolean test(Extent extent, BlockVector3 vector) {
-        return !extent.getBlock(vector).getBlockType().getMaterial().isAir();
+        return !vector.getBlock(extent).getBlockType().getMaterial().isAir();
     }
 
     @Nullable