diff --git a/activesupport/lib/active_support/core_ext/object/extending.rb b/activesupport/lib/active_support/core_ext/object/extending.rb
index 7ac13d3d1a..b8b6970382 100644
--- a/activesupport/lib/active_support/core_ext/object/extending.rb
+++ b/activesupport/lib/active_support/core_ext/object/extending.rb
@@ -1,4 +1,5 @@
 require 'active_support/core_ext/class/removal'
+require 'active_support/core_ext/object/blank'
 
 class Class
   # Rubinius