Cristiano Ronaldo insists he will have no hesitation in stepping up to the plate the next time Manchester United are awarded a penalty.

Chelsea lie in wait at Stamford Bridge on Saturday following the 0-0 draw against Barcelona in the Champions League semi-final first leg last night.

United could have been in even better shape for the return match on Tuesday had Ronaldo not missed from the spot after three minutes.

The club's 38-goal top scorer saw his effort hit the stanchion at the back of the goal after Gabriel Milito had handled the ball.

But he shrugged off the setback and has now set his sights on Chelsea. Victory for United would effectively see them crowned champions for a second successive year, given their superior goal difference.

Ronaldo said: "Next time I get a penalty, I will try and put things right. I am not scared.

"I am always confident. I have 38 goals this season. It is not a problem if I miss one or two. I try to do my best in every game.

"Since I have been in Manchester I have scored 15 or 16 penalties, I think, and missed two. No-one has said anything to me because I always try to score, to play well."

That comment was backed up by Owen Hargreaves, who slotted neatly in at right back after being switched from midfield in a tactical reshuffle.

He said: "Cristiano has scored more than he has missed, so it is fine what happened.

"Maybe he should have had another penalty. But that was always going to be a difficult decision for the referee. He had already given one early in the game and we were the away team."

The contentious incident occurred in the 30th minute when Ronaldo was bundled over by Rafael Marquez but Swiss referee Massimo Busacca did not give the foul.

The Portugal winger was left frustrated and chided the official for his overall performance.

He said: "While you have to respect the decision of the referee, he did not make the best decisions.

"Too many decisions went to Barcelona, he gave us nothing."

Ronaldo is convinced United will carry more of an attacking threat at Old Trafford.

"It wasn't the best game in Barcelona but in Manchester we will try to win," he said.

"I'm sure the return game will be totally different. Barcelona won't keep the ball like they did in this match and we'll create more chances.

"It will be a different game and I'm sure we're going to play better. We are at home, we will have 75,000 people behind us. We will try to play good football and try to win."

Hargreaves believes an all-English final in Moscow against either Liverpool or Chelsea is on the cards.

He said: "We are optimistic as we will play a lot differently than we did at the Nou Camp.

"We will attack Barcelona and see how they deal with it. They had a lot of possession but did not really penetrate us. We had a strategy and played really well."

United will be hoping to go into that crucial encounter on the back of damaging Chelsea's hopes of winning the title.

Ronaldo said: "It will be a tough game but we have a great chance as the team is very confident.

"We do not want to drop any points at Chelsea, so it is important we go for the victory."

United are heading straight to London today from Barcelona to prepare for the title showdown against Avram Grant's side.

Hargreaves added: "It is a great week with three fabulous games. Now it is up to us to do our best at Chelsea and take another step towards retaining our title."

Serbian defender Nemanja Vidic looks certain to remain sidelined after suffering a stomach infection that needed hospital treatment in Spain.