diff --git a/lib/rouge/lexers/gitlab_diff.rb b/lib/rouge/lexers/gitlab_diff.rb
index e136d47df0..c7aaeb9260 100644
--- a/lib/rouge/lexers/gitlab_diff.rb
+++ b/lib/rouge/lexers/gitlab_diff.rb
@@ -15,6 +15,10 @@ module Rouge
           delegate option(:parent_lexer)
         end
       end
+
+      start do
+        option(:parent_lexer).reset!
+      end
     end
   end
 end