A spectacle to set alongside the enduring occasions in Old Trafford's colourful history is promised this evening when Manchester United oppose Juventus in the first leg of their European Champions league semi-final.

Even in decline, Juventus are still the team that excites and motivates all opposition in Europe. And having eliminated Inter Milan with some aplomb in the last round, United believe that they will never have a better chance of beating Juventus.

"If we are honest, this is the tie that we have been preparing ourselves for from day one this season," said Alex Ferguson. "To win the European title, we have always known that we'd have to beat Italian opposition. And when you talk about Italian teams, you tend to start and finish with Juventus.

"Beating Inter Milan was one thing. But Juventus have played in the last three European finals. And when teams are stretched and looking to stay in a game, it's difficult to put a price on experience like that."

A less mature team would almost certainly have fallen by now - with one crisis superseding another, Juventus won just one of their group games. Yet, they still survived to the play-offs in which, wholly in character, they squeezed past Olympiakos with a late goal from Antonio Conte.

United, by contrast, have seldom performed more competently in Europe, profiting from the painful lessons of recent years to present greater discipline at the back and the new cutting edge which Dwight Yorke has provided in attack.

Yorke, capturing the mood of a fine performance, delivered the goals which effectively doomed Inter Milan's title hopes at Old Trafford. Now, in tandem with Andy Cole, he offers the English club a realistic hope of qualifying for the final for the first time since 1968.

To exploit that asset, however, they must first win the critical battle for midfield supremacy. And that focuses the spotlight on, perhaps, the most critical duel of all, the clash of Roy Keane and Zinedine Zidane.

There are those who believe that Zidane's World Cup heroics in France emptied him of much of his stimulation. Victory over Brazil and two goals to boot in a World Cup final, was a difficult act to follow and, undeniably, it has impaired the level of his performances this season.

More than most of his colleagues, he will be grateful for the chance of rescuing his season with a big finish. And in that, there is cause for some disquiet in the Manchester camp.

Yet, in Keane's growing maturity, Ferguson has reaped his biggest bonus. There were those who suspected that the psychological scars of the injury which put the Irishman out of football for much of last season might never fully disappear. Remarkably, he has returned this season, a stronger, more rounded player than ever.

Now, with the weight of expectation bearing more heavily than ever on him, he confesses to being excited at the prospect of pitting his skill against a player he rates as something of an idol.

"Zidane has all of what it takes, skill, strength, vision - the complete player. If we allow him to play, we could be in big trouble," the Irishman admits.

United, unbeaten in three and a half months, will field a full-strength squad, a situation which contrasts sharply with that which obtained on the last occasion they reached the semi-finals, against Dortmund two years ago.

Ryan Giggs has recovered sufficiently from a damaged hamstring to run the left wing and equally significantly, Jaap Stam, now fully settled in the English game and playing much closer to his £10.5 million valuation, is back to preside in central defence.

The most potent force in the earlier part of the season for Juventus, Alessandro Del Piero, has been ruled out with a long-term injury.

Reports yesterday said that Atletico Madrid are set to offer the striker a salary of £5 million a year. in a bid to bring the Italian to Spain.

Del Piero (24) has not renewed his contract with Juventus, but Atletico, according to reports in Spain, would have to still pay the club £10.5 million for the forward on top of personal terms.

Back in the generally less lucrative world of English soccer, a 1-1 draw against Wimbledon last Saturday was scarcely, the ideal preparation for United for tonight's important game. Yet, compared to Juventus's 1-0 defeat by Empoli, a club which hadn't won for four months, it was positively invigorating.

With Zidane, Conte, Paolo Montero and, not least the irrepressible Dutch player Edgar Davids back on duty, the Italians now threaten to be infinitely stronger. But if Keane rules midfield, it can still be another night of merry making in Manchester.