diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index 855192e18926b9972fdd4f120404bed4186c5164..2a1a23a4274e57c400f01f780a8204361668a14a 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Minor tweak to improve performance of ActiveRecord::Base#to_param.
+
 * Observers also watch subclasses created after they are declared. #5535 [daniels@pronto.com.au]
 
 * Removed deprecated timestamps_gmt class methods. [Jeremy Kemper]
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 5aeb8eb3a1dd83871b61ec8bc6b0e43b59abab68..812f30c773b460744580c356f2535bf70879e50a 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -1441,7 +1441,7 @@ def id
       # Enables Active Record objects to be used as URL parameters in Action Pack automatically.
       def to_param
         # We can't use alias_method here, because method 'id' optimizes itself on the fly.
-        id.to_s if id # Be sure to stringify the id for routes
+        (id = self.id) ? id.to_s : nil # Be sure to stringify the id for routes
       end
 
       def id_before_type_cast #:nodoc: