There's no doubt Manchester United can succeed where Liverpool failed by seeing off Bayer Leverkusen in the Champions League. But the outcome of their semi-final will depend on two factors.

First, United will have to play at their absolute maximum. If they're anything off the pace they may be beaten because Leverkusen haven't gone top of the Bundesliga and won against Liverpool, Deportivo La Coruna and Juventus for no reason.

Second, Sir Alex Ferguson will have to hope there are no more major injuries. David Beckham and Roy Keane are already two massive outs and, although United beat Deportivo without them on Wednesday, it would be a real blow to lose other key personnel.

At times such as this you would expect Juan Sebastian Veron to emerge as the world-class player he is. I thought he did that against Deportivo in a role which suits him, central midfield with a ball-winner tucked in alongside.

There were plenty of good signs in the games against Deportivo, with United performing as well in Europe as they have done for three seasons. They played in a free-wheeling manner and they're at their best with that high-risk football.

That United aura could have an impact on Leverkusen. They knew Liverpool weren't going to try to swarm all over them and that, by and large, the initiative would rest with them, but now it will be different, particularly in the first leg at Old Trafford.

United will still need their cutting edge and by then Ruud van Nistelrooy may be back to his best; he looks out of sorts at the moment. I wouldn't be confident if United have only a goal advantage for the return because, with the exception of that 2-0 win at Deportivo, they haven't been great away against top opponents since 1999.

Some people probably wondered how good Leverkusen were after they were rolled over at Highbury in February, losing 4-1. But you have to remember Arsenal were phenomenal that night and went 2-0 up after seven minutes. Their world-class players such as Robert Pires, Thierry Henry and Dennis Bergkamp pulled it out.

Only three days earlier I'd seen Leverkusen rip Borussia Dortmund to pieces in a league game and they're very much the German side in form. They've won eight of their past nine matches, losing the other 1-0 at Anfield.

All the same, there are areas United can exploit. Against Liverpool this week I thought the weakest part of Leverkusen's team was their back line. I wouldn't be surprised if Alex kept Ryan Giggs through the middle to get at Jens Nowotny and Lucio. He might feel there's a certain lack of pace in the centre of that defence and use his quickest player against them. Nowotny struggled a few times with Michael Owen and they wouldn't want people running at them with the ball.

I'm sure Alex will try to get Leverkusen under the cosh early on at Old Trafford and look to steamroller them with bright, adventurous football. What United can't let them do is settle and get the feel for it because they are very capable of moving the ball around.

Away from home I suspect Leverkusen will use just the one striker in Dimitar Berbatov and may not apply much pressure. But they're a powerful side with a lot of self-belief and they do have dangerous players.

Michael Ballack can be quite ordinary but he's a big talent, as he showed by scoring twice against Liverpool. He's been voted the leading player in Germany but maybe we'd not seen that kind of performance until Tuesday.

Yildiray Basturk is industrious and competitive in midfield and Oliver Neuville and Ulf Kirsten are forwards United will have to be careful of in the return. Also, if Leverkusen get their left side going with Diego Placente and Ze Roberto they can create havoc. United will miss Beckham all the more in that respect; the full-back Placente would have been focusing on keeping the England captain quiet and stopping crosses. He'll be relieved not to have that job any more.

United have plenty of options in terms of filling the gap, whether it's Veron, Paul Scholes, Giggs or Ole Gunnar Solskjaer. But I think Beckham's harder to replace than Keane because of his service from wide areas.

Most people would say Keane is United's most influential player but Nicky Butt looks after that role. It was the same when United won the Champions League and Keane was out. Butt is unlucky not to be a regular, although he gets his 20-odd starts a season and he must have played himself bang into the England squad.

Even without Keane and Beckham, United have plenty of European experience and I think that will work in their favour. They've played a lot more of what I call ultimate matches than Leverkusen. Provided they continue this form and avoid further injuries, they should be heading to Hampden Park for the most ultimate match of all.

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