diff --git a/src/ruby/lib/grpc/auth/signet.rb b/src/ruby/lib/grpc/auth/signet.rb
index 1a2e5644e218e3b0b81059fc3e264daba9a2cd9c..a8bce1255c239b8463e610ec9ec7a46cb8b32171 100644
--- a/src/ruby/lib/grpc/auth/signet.rb
+++ b/src/ruby/lib/grpc/auth/signet.rb
@@ -56,6 +56,12 @@ module Signet
         apply!(a_copy, opts)
         a_copy
       end
+
+      # Returns a reference to the #apply method, suitable for passing as
+      # a closure
+      def updater_proc
+        lambda(&method(:apply))
+      end
     end
   end
 end