diff --git a/datafusion/optimizer/src/filter_null_join_keys.rs b/datafusion/optimizer/src/filter_null_join_keys.rs
index c5beb3709281..66e24f5dee7c 100644
--- a/datafusion/optimizer/src/filter_null_join_keys.rs
+++ b/datafusion/optimizer/src/filter_null_join_keys.rs
@@ -50,7 +50,7 @@ impl OptimizerRule for FilterNullJoinKeys {
             return Ok(Transformed::no(plan));
         }
         match plan {
-            LogicalPlan::Join(mut join) if !join.on.is_empty() && !join.null_equals_null() => {
+            LogicalPlan::Join(mut join) if !join.on.is_empty() && !join.null_equals_null => {
                 let (left_preserved, right_preserved) =
                     on_lr_is_preserved(join.join_type);