diff --git a/test/test_related_posts.rb b/test/test_related_posts.rb
index 6111a224..27529bb3 100644
--- a/test/test_related_posts.rb
+++ b/test/test_related_posts.rb
@@ -29,6 +29,7 @@ class TestRelatedPosts < Test::Unit::TestCase
                                                'destination' => dest_dir,
                                                'lsi' => true})
       end
+      any_instance_of(Jekyll::RelatedPosts, :display => nil)
       @site = Site.new(Jekyll.configuration)
     end