"The spirit of the game was not right and [Jose] Reyes was kicked off the pitch. What we saw on the pitch was not right.
"I do not question his [the referee's] honesty - he did his job as well as he could - but he did not protect the spirit of the game well enough.
"Sometimes if you miss the first step, it becomes very difficult to control. I think he would even come out and acknowledge that it was not a penalty. When you watch it, the dive [by Wayne Rooney] is delayed because the ball is lost.
"I'll admit we didn't have the best of games but we tried to play. I am not responsible for the way United approach a game. But nothing we did in our approach to the game was wrong or immoral on our side.
"And what makes the situation worse today is that he [Van Nistelrooy] said it was a 50-50 tackle. I cannot say much more than that, the FA do what they want.
"I don't think I have said anything wrong.
"I said we feel a little bit robbed and I still feel that.
"The referee made a genuine and honest mistake with the penalty but you cannot say you feel happy because he made it."
Wenger also revealed today that Sol Campbell (Achilles), Thierry Henry (Achilles), Patrick Vieira (ankle) and Cole (knee) all suffered injuries on Sunday.
