diff --git a/actionpack/lib/action_view/helpers/url_helper.rb b/actionpack/lib/action_view/helpers/url_helper.rb
index 489b96856d..8cb22df280 100644
--- a/actionpack/lib/action_view/helpers/url_helper.rb
+++ b/actionpack/lib/action_view/helpers/url_helper.rb
@@ -619,7 +619,9 @@ module ActionView
         end
 
         def add_method_to_attributes!(html_options, method)
-          html_options["rel"] = "nofollow" if method.to_s.downcase != "get"
+          if method && method.to_s.downcase != "get"
+            html_options["rel"] = "#{html_options["rel"].to_s} nofollow".split(" ").uniq.join(" ")
+          end
           html_options["data-method"] = method
         end
 
diff --git a/actionpack/test/template/url_helper_test.rb b/actionpack/test/template/url_helper_test.rb
index 1e54f0174c..a70c02a429 100644
--- a/actionpack/test/template/url_helper_test.rb
+++ b/actionpack/test/template/url_helper_test.rb
@@ -245,6 +245,13 @@ class UrlHelperTest < ActiveSupport::TestCase
     )
   end
 
+  def test_link_tag_using_post_javascript_and_rel
+    assert_dom_equal(
+      "<a href='http://www.example.com' data-method=\"post\" rel=\"example nofollow\">Hello</a>",
+      link_to("Hello", "http://www.example.com", :method => :post, :rel => 'example')
+    )
+  end
+
   def test_link_tag_using_post_javascript_and_confirm
     assert_dom_equal(
       "<a href=\"http://www.example.com\" data-method=\"post\" rel=\"nofollow\" data-confirm=\"Are you serious?\">Hello</a>",