Football: United must swat the Louse

Champions' League: Two powerful reasons why the fortunes of Ferguson and Vialli are under threat; John Carlin charts the rise of a little man for the big occasion

IF THERE is one message Alex Ferguson will want to impress upon his accident-prone defenders as they step out for their Champions' League match on Wednesday against Valencia, it will be this: Beware the Louse.

Claudio is his real name, Claudio Lpez. But Valencia's Argentine striker, a player with the habit of rising to his pestilential best on the big occasions, is best known in Spanish football as El Piojo, the Louse.

His compatriot, Fiorentina's Gabriel Batistuta, hammered one nail into Manchester United's European Cup ambitions 10 days ago. Unless the champions exercise extreme caution, Lpez is the man who could bury them at Old Trafford this week. The player United will entrust with the task of stopping him will be, no doubt, Jaap Stam. If the mighty Dutchman has one rival for the title of best central defender in Europe, it is another Dutchman, Barcelona's Frank de Boer. Stam should talk to de Boer about Lpez. Or perhaps he shouldn't.

Lpez overran de Boer towards the end of last season in a remarkable spell of three Valencia victories in 10 days against Barcelona - home and away quarter-final legs in the Spanish Cup and a league game at the Nou Camp. Marked by the more accomplished of the Dutch twins, Lpez scored six goals, two in each game. The goal tally over three amazing matches was Valencia 11, Barcelona seven. Then they defeated Real Madrid 6-0 (two more Lpez goals) in the semi-final of the Cup, before going on to win it.

With the Old Trafford test around the corner, it is worth pointing out this habit Lpez, and Valencia, have of playing above themselves in big games. Because they lie 15th in the Spanish league at present, having beaten Barcelona 3-1 two weeks ago. They also won their group in phase one of the Champions' League, with three points to spare, having not lost a match against Bayern Munich, PSV Eindhoven or Rangers. And then they smashed the French champions, Girondins of Bordeaux, 3-0 in the first game of phase two.

Lpez, Valencia's top scorer in Europe, is a left-sided version of Michael Owen. And, at 25, more accomplished. He scores 90 per cent of his goals and strikes 90 per cent of his shots with his left foot. He is accurate from long range but tends to thread and curl his goals from inside the area, often after wriggling his way through a couple of tackles, or after beating the offside trap with an electric run.

But he is not, as one might say of Owen, a chronically one-footed player. In the 3-1 victory over Barcelona, Lpez surprised de Boer once again by making as if to strike with his left, then veering away to tuck the ball into the corner with his right.

If Manchester United manage to contain Lpez they will go a long way to avoiding catastrophe on Wednesday. But there is more to Valencia than the Louse. Although his regular strike partner, Romania's Adrian "the Cobra" Ilie, will miss the match after spending most of last week in hospital for treatment to gallstones, on the left, in Ryan Giggs's position, Kily Gonzalez has the power and guile one comes to expect from a member of the Argentina international side.

Rigorously marshalled by their shrewd, hard-bitten manager, Hector Cper, another Argentine, the Valencia defence will be a tough nut for United to crack. Average age 32, the multi-national back four of Angloma (France), Djukic (Yugoslavia), Pellegrino (Argentina) and Carboni (Italy) are a tight, intelligent unit who will not be overawed either by Old Trafford or - having subdued Figo, Kluivert and Rivaldo - by Beckham, Yorke and Cole.

But the player who might interest Ferguson more than all the others is the Basque team captain Gaizka Mendieta. And for more reasons than one.

Mendieta is the midfield general every modern manager dreams of. A tirelessly physical team player, he makes timely tackles in the penalty area, dominates the centre of the pitch, and scores goals. A Spanish international, Mendieta has played at right-back for Valencia, at centre-half, in central midfield and in Paul Scholes's inside-forward position. Often he plays all at once.

He scored the two best goals of last season in Spain. One, in the Cup final, a replica of Pele's famous goal in the 1958 World Cup - a lob over a defender in the penalty area and a volley, before the ball touched the ground, into the back of the next. The other, at the Nou Camp, was also a volley, a 30-yard rocket straight from an Ilie corner.

The second reason, this week's game aside, why Ferguson may find Mendieta of intense interest is that, in the event of Roy Keane leaving at the end of the season, here is a candidate to fill the mighty Irishman's shoes. Less inspirational than Keane, Mendieta might be. But technically, he is more gifted and, at 25, still has room to improve. Besides, he is rarely injured and in the whole of last season collected only five yellow cards.

United's Champions' League fate will turn this Wednesday on a midfield battle where the pressure will be on Keane to show Mendieta who is the man and who is the boy. And on whether United avoid doing a Barca and keep the Louse out of their hair.