Ruud dusted himself off after the decision, to fire home his thirtyninth goal of the season, leaving him in contention for the European Golden boot award for the season.
"We were always up against it from that moment. We'd been playing well and had created a couple of chances.
"But the first goal of any match is important, especially when you are playing Manchester United, and when the referee makes a decision like that, you know you're in for a difficult game.
"It was a joke decision and it cost us the game. In fact, we should have had a penalty, but Darren Bent tried to stay on his feet when he was fouled. Van Nistelrooy, on the other hand, went down looking for a penalty."
Titus Bramble, the man penalised by referee Rob Styles, agreed with his boss: "I don't think it was a penalty. I just stood my ground. The ball would have gone over his head, but there must have been a tangle of legs.
"It's cost us the game. It is so disappointing for us because we have played really well in the last few games."
Styles said after the game that he saw a push by Bramble, something that few others were aware of with the exception of the Manchester United boss. Alex Ferguson backed Styles' decision: "I appealed for a penalty when I first saw it. It was the first thing I thought of when Ruud went down. It looked like a penalty from where I was sitting."