Manchester United manager Alex Ferguson says that his team will need to produce their best-ever performance if they are to overturn a 3-1 first-leg deficit and beat Real Madrid in Wednesday's Champions League quarter-final second leg.

The holders and nine-times winners are favourites to progress to a semi-final meeting with either Barcelona or Juventus, who resume hostilities on Tuesday in Spain level at 1-1.

Another Spanish-Italian clash takes place on the same night as Valencia host Inter Milan looking to come back from a 1-0 first leg defeat.

The winners of that game will play either AC Milan or Ajax Amsterdam, who play in the San Siro on Wednesday after a goalless opener.

It might have been disappointing fare in the Amsterdam Arena two weeks ago but there was no shortage of entertainment in the Bernabeu.

Real Madrid turned on the style to race into a 3-0 lead over United, with two goals for Raul and one for Luis Figo.

With Zinedine Zidane showing all his tricks and United playing like rabbits caught in the spotlight, the tie looked all over five minutes into the second half.

However, Ruud van Nistelrooy's header, his 13th European goal of the campaign, gave United a lifeline.

They returned from Spain to thrash Newcastle United 6-2, hold title rivals Arsenal to a 2-2 draw and beat Blackburn Rovers 3-1 on Saturday -- to further lift morale at the club.

Now, instead of acknowledging the superiority of Real's multi-millionaire squad, all the talk is of how Zidane's tricks count for nothing and how an early goal will change the game.

"It's a hell of a task, but we're capable of it... My hope is to go 1-0 up by halftime because, if we can do that, the whole complexion of the game changes," said Ferguson.

The Scot is demanding that his players put in the tackles that they failed to muster two weeks ago and reminding everybody that United had plenty of chances in the first leg.

"If we are going to pull this one off we are going to have to perform our best ever," he said.

United are without defender Gary Neville and Paul Scholes, both suspended, and the absence of Scholes will be a particular blow as the England midfielder has been in the form of his life in recent weeks and scored twice against Blackburn.

Real were kicking themselves for not killing the game off when they were in control and they have also stuttered domestically since.

However, they also know that they can score anywhere and one goal at Old Trafford should see them through.

BARCELONA FAVOURITES

Barcelona already have their away goal against Juventus and start favourites to progress.

They have won 13 and drawn two of their 15 games in Europe this season and a win or 0-0 draw in the Nou Camp will see them through.

They stopped their domestic rot with a 1-1 away draw against Real Madrid on Saturday while Juventus remained on course for the Serie A title with a 2-1 win over AS Roma.

Inter Milan, chasing Juve hard in Italy, have never reached a Champions League semi-final -- they were last in the European Cup semis 23 years ago -- but will end that barren spell if they can keep Valencia at bay.

Inter warmed up with a 1-0 win over Brescia secured by Hernan Crespo's injury time goal but Valencia lost 1-0 at Valladolid to say goodbye to their slim Spanish league hopes.

Emre Belozoglu of Inter and David Albelda of Valencia are both suspended following their red cards after a scuffle in the first leg.

Ajax travel to Italy in reasonably confident mood, knowing that they have scored in most of their away games in Europe this season and aware that Milan will be unlikely to repeat their defensively-minded tactics in front of their own fans.

Milan start favourites but they are struggling for consistency. They followed up last week's derby win over Inter with a shock 1-0 home defeat to lowly Empoli on Saturday and are without suspended midfielder Gennaro Gattuso on Wednesday.