Boy Blunder - Fall guy Ronaldo misses a penalty but vows to punish Barca in the return

Ronaldo, the scorer of 38 goals this season, missed a second-minute penalty at the Nou Camp where defiant United were fortunate to earn a 0-0 draw in the first leg of the semi-final.

I don't believe it! Cristiano Ronaldo is left stunned after his second-minute spot-kick miss last night

But the Portugal winger immediately vowed to make amends when the teams meet in Manchester next Tuesday. He said: "I did not change my style of taking the penalty. I have scored in that corner before this season. Now I will score next week in Manchester.

"It was a difficult game as they kept the ball well, but we defended very well and a 0-0 draw away from home is a good result."

United struggled to keep possession of the ball after early chances but could have had another penalty when Ronaldo seemed to be fouled in the 30th minute. He added: "I don't understand why the referee did not give me the second penalty but it won't matter."

With United defender Nemanja Vidic missing out after spending a night in hospital with a stomach infection, United had to reshuffle their defence, with Owen Hargreaves filling in at right back.

Vidic, who was too ill even to attend the game, is now doubtful for Saturday's Barclays Premier League crunch game at Chelsea but manager Sir Alex Ferguson remained upbeat after last night's showing.

He said: "Barcelona have a lot of possession in a lot of games, so it was not unusual and we were satisfied that we kept a clean sheet. I thought it was an exceptional performance to do that.

"We are a bit disappointed in the way we tried to turn defence into attack because we are normally good at that and tonight it didn't happen. That's caused us some problems.

"We hope the penalty miss doesn't affect us too much and the game starts at Old Trafford now. A score draw or a defeat puts us out but the bonus is that if we win we are through. With our record at home and the atmosphere there will be on the night, then it means we have a very good chance.

"What was interesting is that the Barcelona supporters were happy with the performance of their team even though they didn't win.

Their support was terrific and hopefully we will have the same support at our ground on Tuesday.

"Vidic was very sick and is touch-and-go for the weekend. He was 24 to 36 hours without eating. He had some soup this afternoon, but wasn't ready to play. But I thought we did very well (without him) and the pleasing thing is that Barcelona did not make great chances."