The referee considered this dangerous tackle by Madrid keeper early in the match to be an accident (unintentional), and he gave Nani a red for an accidental collusion.

Vidic headed a United corner, Madrid keeper Diego Lopez came late, missed the ball, and gave Vidic a heavy punch. Vidic went own immediately.

Nani went for the ball, had his eyes on it, Arbeloa could have avoided Nani, be he decided to run into Nani from his (Nani) blind side. Then there was an unintentional (accidental) collusion. Nani got a red for that, while Diego Lopez walked free.