But Premiership hero Ronaldo declared: "I'm used to the booing. Last season I was booed in all the stadiums in England.
"The booing doesn't kill me. But it was a beautiful experience to play in Barcelona.
"I missed, that's football. There's no drama. If there's a penalty in Manchester, I'll score - let nobody doubt that.
"Sometimes you score, sometimes you miss. Since I've been at United, I've scored 15 or 16 penalties and missed three. I think that's not bad.
"I've scored 38 goals this season and I think there's no problem if I miss one.
"It will be different in Manchester because they'll also have to take risks. On Wednesday they kept the ball well but I think the advantage is with us."