"He will be criticised for that because when you pay £30m for a player everyone thinks you should be able to score from a penalty kick," Fergie has said.
"But it's just not as simple as that.
"He had his injury and missed a couple of games, but he came on and did well in the game.
"He's disappointed to miss a penalty, of course. He was upset, but it was a disappointed dressing room.
"You lose in a semi-final - and it's the first we've lost - and that's not easy to take. Anyone can lose on a penalty kick, I've lost many like Sunday.
"I don't see it as a defining part of my career because anyone can win or lose them."