diff --git a/actionmailer/lib/action_mailer/test_case.rb b/actionmailer/lib/action_mailer/test_case.rb
index bdda66b32a..766215ce96 100644
--- a/actionmailer/lib/action_mailer/test_case.rb
+++ b/actionmailer/lib/action_mailer/test_case.rb
@@ -16,7 +16,8 @@ module ActionMailer
 
       include ActiveSupport::Testing::ConstantLookup
       include TestHelper
-      include Rails::Dom::Testing::Assertions
+      include Rails::Dom::Testing::Assertions::SelectorAssertions
+      include Rails::Dom::Testing::Assertions::DomAssertions
 
       included do
         class_attribute :_mailer_class
diff --git a/actionmailer/test/base_test.rb b/actionmailer/test/base_test.rb
index 0da22f591f..396d0a95b5 100644
--- a/actionmailer/test/base_test.rb
+++ b/actionmailer/test/base_test.rb
@@ -10,7 +10,7 @@ require 'mailers/proc_mailer'
 require 'mailers/asset_mailer'
 
 class BaseTest < ActiveSupport::TestCase
-  include Rails::Dom::Testing::Assertions
+  include Rails::Dom::Testing::Assertions::DomAssertions
 
   setup do
     @original_delivery_method = ActionMailer::Base.delivery_method