diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb
index 869eebfa348d7f57521c3ff5603ed79d76cd48d9..a8a52867ceefdd3c60e1419be990daca6dd8cd20 100644
--- a/activerecord/lib/active_record/relation/calculations.rb
+++ b/activerecord/lib/active_record/relation/calculations.rb
@@ -197,7 +197,7 @@ def operation_over_aggregate_column(column, operation, distinct)
 
     def execute_simple_calculation(operation, column_name, distinct) #:nodoc:
       # Postgresql doesn't like ORDER BY when there are no GROUP BY
-      relation = except(:order)
+      relation = reorder(nil)
 
       if operation == "count" && (relation.limit_value || relation.offset_value)
         # Shortcut when limit is zero.
diff --git a/activerecord/test/cases/relation_scoping_test.rb b/activerecord/test/cases/relation_scoping_test.rb
index 864b3d4846913ee127cfe7617c31e0ba6bb4a879..c21560256727df690e89c54c159cdd573fc24907 100644
--- a/activerecord/test/cases/relation_scoping_test.rb
+++ b/activerecord/test/cases/relation_scoping_test.rb
@@ -462,4 +462,8 @@ def test_unscoped_with_named_scope_should_not_have_default_scope
     assert DeveloperCalledJamis.unscoped.poor.include?(developers(:david).becomes(DeveloperCalledJamis))
     assert_equal 10, DeveloperCalledJamis.unscoped.poor.length
   end
+
+  def test_default_scope_order_ignored_by_aggregations
+    assert_equal DeveloperOrderedBySalary.all.count, DeveloperOrderedBySalary.count
+  end
 end