Index: lib/ostruct.rb
===================================================================
--- lib/ostruct.rb	(revision 34752)
+++ lib/ostruct.rb	(working copy)
@@ -190,8 +190,8 @@
   #
   def delete_field(name)
     sym = name.to_sym
+    singleton_class.__send__(:remove_method, sym, "#{name}=")
     @table.delete sym
-    singleton_class.__send__(:remove_method, sym, "#{name}=")
   end
 
   InspectKey = :__inspect_key__ # :nodoc:
Index: test/ostruct/test_ostruct.rb
===================================================================
--- test/ostruct/test_ostruct.rb	(revision 34752)
+++ test/ostruct/test_ostruct.rb	(working copy)
@@ -57,9 +57,10 @@
     o.a = 'a'
     assert_respond_to(o, :a)
     assert_respond_to(o, :a=)
-    o.delete_field :a
+    a = o.delete_field :a
     assert_not_respond_to(o, :a, bug)
     assert_not_respond_to(o, :a=, bug)
+    assert_equal(a, 'a')
   end
 
   def test_method_missing_handles_square_bracket_equals