diff --git a/lib/sidekiq/extensions/action_mailer.rb b/lib/sidekiq/extensions/action_mailer.rb
index 18469e72..c1688b94 100644
--- a/lib/sidekiq/extensions/action_mailer.rb
+++ b/lib/sidekiq/extensions/action_mailer.rb
@@ -14,7 +14,7 @@ module Sidekiq
 
       def perform(yml)
         (target, method_name, args) = YAML.load(yml)
-        msg = target.__send__(method_name, *args)
+        msg = target.public_send(method_name, *args)
         # The email method can return nil, which causes ActionMailer to return
         # an undeliverable empty message.
         msg.deliver if msg && (msg.to || msg.cc || msg.bcc) && msg.from