IN SOME WAYS IT IS APPROPRIATE that the Major League Soccer Cup final — the biggest weekend in football in the United States — should be overshadowed by two news items, both of which are based on hypotheticals.

Even as New England Revolution and Houston Dynamo contested the right to become MLS champions, the spotlight was shared with Freddy Adu’s imminent two-week training session (whatever you do, do not call it a “trial”) at Manchester United, as well as the approval of what was immediately dubbed the “Beckham Rule”. Both are geared towards the future of football in the US, both are steps in the grand design to turn the beautiful game into a viable and commercially attractive pursuit.

The “Beckham Rule” will allow each club to go above and beyond the league’s wage cap of £1.05 million per team to secure the services of one star player. Only £210,000 of the player’s annual wage will count towards the salary cap.

With Beckham’s contract situation at Real Madrid unresolved (his deal expires in June), it is seen as a mechanism for allowing clubs such as the Los Angeles Galaxy, who have been linked with the former England captain, to secure such a player’s services.

MLS has allowed various wage loopholes in the past (enabling the signing of the likes of Roberto Donadoni and Carlos Valderrama), but this is a significant break from the safety-first tradition of the league’s backers. It means that, theoretically, there is nothing to stop a club such as the New York Red Bulls from matching or surpassing the wages of Ronaldinho or Wayne Rooney.

Of course, capturing the American mainstream is not only about signing high-priced foreign stars (after all, MLS’s precursor, the North American Soccer League, did that with Pelé, Franz Beckenbauer and Johan Cruyff — and ended up in bankruptcy a few years later). The country needs to produce its first big, bona fide superstar and, until recently, all the chips were on Adu’s 17-year- old shoulders.

Born in Ghana but raised in the US from the age of 8 after his mother won the green card lottery, Adu has been in the spotlight since he was 12, when Inter Milan offered him and his family a package worth close to £500,000 to move to Italy.

Adu turned them down and became the US Soccer Federation’s biggest development project. At 13, he signed a £550,000 endorsement contract with Nike and starred in television advertisements with Pelé; at 14 he made his professional debut for DC United, becoming the youngest professional athlete in the history of American sport; at 15 he started going out with his first celebrity girlfriend, the R&B star, JoJo; and at 16 he won his first cap for the US.

A meteoric rise? In some ways, yes. But it is equally true that his development has not been as rapid as some expected. Certainly not the sponsors and the American public, some of whom have begun to wonder what the hype is all about.

In his first two seasons in Washington, Adu started a shade more than half the club’s league games. This year was his first as a week-in, week-out regular and results have been mixed. While he has more than held his own at one of MLS’s better clubs, doubts remain about whether he can go to the next level. Just because he got this far by the age of 17, it does not mean that he will continue to improve at the same rate.

Yet that is what his backers demand and what football in the US is counting on. Originally the plan was for him to go to the World Cup finals in Germany in the summer, which would have made him the same age as Pelé in 1958, a player with whom he shares a vague physical resemblance, but, more important, a person to whom the American public can relate. Bruce Arena, the US coach, shut the door on Adu early, however, (he still has only one international cap) and it became clear that he would have to be patient.

A big part of Adu’s problem is figuring out where to play him. He is an outstanding dribbler blessed with good movement and vision, but he is also very left-footed and is too easily outmuscled. He is officially listed as 5ft 9in, but that appears generous. What is more, unlike other pint-sized footballers, he has neither the stocky build nor the low centre of gravity to prevent opponents from knocking him off the ball.

After a spell as an attacking midfield player, Adu spent most of the season wide on the right in DC United’s 3-5-2 formation, a curious choice for a left-footed player who does not seem to have the physical tools to cover the flank on his own.

So what should we make of his impending spell with Manchester United? Adu’s advisers have privately called it a “trial”, while DC United insist on terming it a “training opportunity”. As for MLS — which owns his registration, as it does for all US-based players — it seems to be annoyed by the whole thing. One league official, quoted anonymously in the US, said: “This is the same old Freddy bulls***.”

The league’s ambivalent attitude towards Adu is not hard to understand. On the one hand, moving abroad might help to turn him into the superstar the sport in the US needs. On the other, it would deprive MLS of its most familiar face while, at the same time, distracting attention from what should have been the league’s showpiece final.

It is tempting to draw a link between United’s American owners, the Glazer family, and Adu’s appearance at their Carrington training ground and conclude that it is a publicity-seeking vehicle. Yet United have not toured the US since the Glazers took charge and, beyond the fact that the player and the club are sponsored by Nike, there is no real connection.

Still, Adu’s spell at Carrington will provide United and other European clubs a chance to assess the player. And it will, one hopes, give him a clearer picture of his limits and his future.

Those who know Adu say that he is bright and self-aware. If that is the case, he will be equally aware of the “Kournikova trap”. The Russian tennis star, Anna Kournikova, enjoyed attention and endorsements that far outweighed her standing on the tennis court. Adu does not want to go down that road, partly because he believes that, unlike Kournikova, he does have the skills to be among the best in the world and partly because, unlike Kournikova, he knows that he cannot get by on his looks alone.

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