6 into 1 won't go

The men's draw at the US Open is beautifully set up this year. For the first time in ages, the natural hierarchy seems unclear, with Nadal's prolonged absence qualifying both the rankings and the achievements of Roger Federer and Andy Murray. But it's impossible to say how much.

Right the way down to Del Potro at No. 6, the rankings don't tell the full story. If the Argentine can overhaul his fitness, he should emerge as the main challenger to Murray and Nadal in the longterm. Roddick is in his best run of form since winning the US aged 19, and his resurgence marks a genuine development of his game. Djokovic is stagnating but not regressing, while Nadal at No. 3 looks like a misprint. Murray is probably the most consistent player on the Tour, but has developed an unfortunate knack of bringing out the very best in opponents at crucial points in Slams - for Verdasco in Melbourne, read Gonzalez at Roland Garros and Roddick at Wimbledon. Coasting through the early rounds of majors will start to look ominous if he continues this pattern. A first Grand Slam win may open the floodgates - he seems to have the determination to overhaul a waning Federer, but probably not the aggression to better a fully fit Nadal. So each would be king, but it's hard to see who should be.

Federer's case is the most interesting. It seems bizarre in the context of his achievements and previous invincibility that he could now be No. 1 without really deserving it, as he's quite keen on reminding everyone. The gracious, easy figure of old has faded away both on and off the court, replaced by a man who not only believes his own headlines, but seems quite keen on writing them. Nominally world No. 1, "RF" has won ugly this year against a depleted field, but you won't catch him acknowledging it. Instead he repeatedly places lucky escapes and strangled victories in the context of what he calls his "crazy" achievements. It would be no great surprise to see him enter Center Court next week on a horse-drawn cart in the shape of a '16'. This need to frame his own legacy is a habit that has developed as his grip on power has loosened. Anyone who saw him sunken after the Australian Open final knows that Nadal has got inside his head, and that the two subsequent major wins were by default. It is of course true that you can only beat who's put in front of you, but it's equally true that you can acknowledge a crucially weakened field in the moment of victory.

Who will be on top one year from now? Any from Del Potro, Murray, Nadal and Federer seems equally plausible, with Djokovic needing fresh impetus and Roddick probably having reached his personal xenith. It's exciting, it starts next week, and it is to be hoped that Nadal returns to form, so that whoever is world No. 1 can wear his crown with undisputed pride.