diff --git a/lib/sidekiq_unique_jobs/middleware/server.rb b/lib/sidekiq_unique_jobs/middleware/server.rb
index 1807a2f8..fb7f1f52 100644
--- a/lib/sidekiq_unique_jobs/middleware/server.rb
+++ b/lib/sidekiq_unique_jobs/middleware/server.rb
@@ -6,7 +6,7 @@ module Middleware
     #
     # @author Mikael Henriksson <mikael@mhenrixon.com>
     class Server
-      include Sidekiq::ClientMiddleware if defined?(Sidekiq::ServerMiddleware)
+      include Sidekiq::ServerMiddleware if defined?(Sidekiq::ServerMiddleware)
 
       # prepend "SidekiqUniqueJobs::Middleware"
       # @!parse prepends SidekiqUniqueJobs::Middleware