Were hunger alone enough to win a Grand Slam title, Rafael Nadal [Images], Andy Roddick [Images] and Lleyton Hewitt [Images] could all claim to be salivating favourites for this year's U.S. Open men's singles crown.

Appetite is probably the only quality they possess in at least equal measure to the player who again starts a tennis major as the firm favourite to win it -- Roger Federer [Images].

The preparations of the Swiss world number one for the defence of his Flushing Meadows title speak volumes.

While his rivals toiled for form and fitness on the punishing U.S. hardcourt circuit, Federer put his feet up.

A six-week break after his third successive Wimbledon [Images] triumph in July allowed the 24-year-old to rest the sore foot arches that are a side effect of his extraordinary success this season.

Federer has won 64 of his 67 matches in 2005 and his emphatic victory at the Cincinnati Masters after a six-week break following Wimbledon was his ninth title of the year.

He has been number one for 83 consecutive weeks, the seventh longest reign at the top of the rankings in history. Andre Agassi [Images] (101) and Bjorn Borg [Images] (109) are in his sights and Federer is more than comfortable in their company.

"This is a great season so far," Federer said. "I'm really happy with the way I've played. If you look at my record, it's fantastic.

"When it comes down to a Grand Slam, you've got to be ready. I think I'm ready, that's why I took a rest. Mentally and physically I'm feeling good."

BIGGEST THREAT

The biggest threat to Federer at Flushing Meadows may come from the only player who appears to be closing the gap on the Swiss rather than losing ground, 19-year-old Spaniard Nadal.

The increasingly muscular Mallorcan has jumped from 51 at the start of the year to number two in the rankings with mesmerising tennis that has brought him a first Grand Slam title, the French Open [Images] where he beat Federer in the semi-finals.

The Swiss, however, is almost as much a novice on clay as Nadal is on a hardcourt and the Spaniard will have noted that Federer delights in quickly avenging his rare defeats.

He beat Russian Marat Safin [Images], his conqueror in the Australian Open [Images] semi-finals at the start of the year, in the Halle final in June.

The memory of Federer's only other loss, to Frenchman Richard Gasquet in the Monte Carlo quarter-finals in April, was erased the following month in the Hamburg Masters final.

Nadal showed he is quickly learning the art of hardcourt tennis by winning the Montreal Masters this month. His rapid ascent has ousted Hewitt and Roddick from their rankings position on the shoulder of Federer.

"I feel good," the Spaniard said. "I feel tough mentally. That's the most important thing, because if I feel tough mentally, I feel good physically."

Hewitt has endured a frustrating year. He was denied a much-coveted victory in his home grand slam by Safin in the Australian Open final, and injuries and illness have disrupted his momentum.

Typically, he remains optimistic. "I always feel pretty comfortable when I get to Flushing Meadows," he said. "I really like the atmosphere and the court surface there. I think the whole tournament really suits my game and my attitude as well."

SEPTEMBER 11

Unlike Nadal, he is already firmly under Federer's spell, having been thrashed by the Swiss in last year's U.S. Open final and the Wimbledon semi-finals in July.

The same can be said of Roddick, who turns 23 on the first Tuesday at Flushing Meadows.

The manner in which Federer embarrassed him in the Wimbledon final and again in the Cincinnati Masters last weekend suggested the American will need more than the raucous backing of his home fans to live with the world number one.

Roddick, the 2003 champion, has meandered to number four in the rankings but said: "It doesn't bother me. I'm in the mix.

"My goal is that I'm still contending for majors and I've put in good results in majors this year, that's my main concern."

Safin is probably the only other realistic contender, although his fitness is in question following his post-Wimbledon knee operation.

Whoever makes it to the final, the climax of the men's singles promises to be especially emotive, falling as it does on the fourth anniversary of the September 11 attacks on New York.

Should Agassi, the 35-year-old who appears on the brink of retirement, reach the final, the intensity on the cavernous Arthur Ashe court would reach almost unbearable levels.

The idea seemed absurd a few weeks ago with Agassi racked by back pain.

However, in winning the Los Angeles Open and reaching the final of the Montreal Masters in August the father-of-two showed he is not quite ready to swap professional sport for full-time parenting.

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