diff --git a/lib/sidekiq/middleware.rb b/lib/sidekiq/middleware.rb
index ede25d1d..db80b6ab 100644
--- a/lib/sidekiq/middleware.rb
+++ b/lib/sidekiq/middleware.rb
@@ -36,7 +36,7 @@ module Sidekiq
       end
 
       def self.chain
-        @chain || default
+        defined?(@chain) ? @chain : default
       end
 
       def self.retrieve