Nani dived in with a tackle on Stiliyan Petrov after just 30 minutes of the game and referee Peter Walton had no hesitation in showing the player a straight red which carries a three match ban.
"It was a sending off," said the United boss.
"It was a red card. It was a naive tackle. He is not a malicious player but he has gone in with his foot raised off the ground and we cannot complain about it.
"We should have had a foul seconds before when Agbonlahor came in with his foot up on Wes Brown's ribs.
"That was disappointing but we have no argument at all with the red card."