Zabaleta was on the end of a late challenge from Welbeck and a stray elbow from Fellaini during City's 3-0 win, and the right-back has revealed that he was surprised that United were not reduced to nine men.
The 29-year-old told Sky Sports News: "They were two bad challenges. I have seen them on the television screen in the dressing room.
"The first one was a very dangerous tackle by Welbeck. I was very lucky because I could have broken my leg.
"I think that the second one was an elbow from Fellaini. I think this was was also a red card, but at the end of the day, we show respect for the referee decision."
Manchester City's victory takes them to within three points of Premier League leaders Chelsea.