1 files changed, 5 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index 323f25e37e..1e2d6c4f1e 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -27,16 +27,16 @@ module ActiveRecord
           raise NotImplementedError
         end
 
-        # The name of the key on the model which declares the association
-        def owner_key_name
-          raise NotImplementedError
-        end
-
         private
           def options
             reflection.options
           end
 
+          # The name of the key on the model which declares the association
+          def owner_key_name
+            reflection.join_foreign_key
+          end
+
           def associated_records_by_owner(preloader)
             records = load_records do |record|
               owner = owners_by_key[convert_key(record[association_key_name])]