United boss Sir Alex Ferguson was upset with the decision claiming that Ronaldo had said that he thought he had heard the referee's whistle blow prior to handling the ball.
"I've seen it again and he was trying to protect himself from the ball hitting his face. He may have got a little shove as well," Fergie said after United's 1-0 win at Eastlands
"He thought he'd heard the referee's whistle. But I'm not going to get into the refereeing, we'd be here all day.
Ronaldo will now serve an automatic one match suspension ruling him out of the cup tie against Blackburn at Old Trafford on Wednesday night.