Roger Federer is poised to advance to within one Grand Slam of Pete Sampras's record of 14 in the year's opening major tournament at the Australian Open, which gets underway here on Monday.
The Swiss champion has been unchallenged as world No.1 since February 2004 and won three of last year's four Grand Slams for the third time in four years.
The "Fed Express" is bidding for a hattrick of Australian titles and is on an unbeaten 14-match roll in Melbourne.
It has all the appearances of the 26-year-old's 13th Grand Slam crown, edging him closer to the 14 Sampras won from 1990 to 2002.
Just who can dethrone Federer is the question constantly posed in men's tennis, and his main rivals appear to be the younger brigade, headed by world No.2 Rafael Nadal, third-ranked Serbian Novak Djokovic and British No.9 Andy Murray.
Federer has met their challenges, winning all but three of the last five years of Wimbledon and the Australian and US Opens, but failing to master Nadal on the clay of Roland Garros in the last two French Opens.
It may come down to health problems with Federer lining up for his 33rd consecutive major tournament.
The Swiss star was forced to withdraw with a virus from this week's Kooyong Classic warm-up event after coming down with a bug shortly after arriving from Dubai, where he trains in the off-season.
But he says doctors expect him to be fit for Monday.
"The doctors have advised me that I should take a couple of days off and recuperate so that I am able to be 100 percent for the start of the Australian Open," he said.
Federer came to Australia early to familiarise himself with the new Plexicushion courts, which have replaced the Rebound Ace hardcourts at Melbourne Park.
He has warned his would-be challengers that he intends to stay in tennis for the long haul.
"I have put the priority on longevity. I've always had an eye to the future and would like to continue playing as long as possible to play against as many generations as possible. I am in it for the long run," he said.
Nadal had a setback in his Australian Open buildup when he suffered an embarrassing defeat to Russian Mikhail Youzhny 6-0, 6-1 at the Chennai Open final.
The 21-year-old Spaniard called for a trainer during the second set, but insisted he was not injured.
"I look forward to going to Melbourne and training hard for the Australian Open. It is a tournament which interests me a lot," Nadal said.
Nadal reached the quarter-final at the Open last year, but did not progress beyond the fourth round in two earlier appearances in Melbourne.
"In a normal moment in the history of tennis, I'd have been number one in the rankings," he said.
"I'm not worried about Roger, he is better than the other guys at the moment. But a lot of young guys are coming from behind at the present time."
Djokovic blamed burn-out after last year's breakthrough season petered out at the Masters Cup in Shanghai.
The Serb played an exhaustive schedule of 103 singles and doubles matches in 2007, more than any other top-10 player.
Now refreshed, he will be looking to mount a serious challenge to Federer here after having chances against the Swiss in last year's US Open final.
Murray won the Qatar Open on his way to Australia and the 20-year-old Scot is expecting a place in the top 12 seedings in Melbourne.
"If you're ranked between 13 and 16, you get drawn to play the top four seeds in the fourth round of the Australian Open," he said.
Andy Roddick and James Blake have had a shortened off-season after leading the United States to a 4-1 win over Russia in the Davis Cup final in Portland, Oregon, early last month.
Roddick has not been beyond three semi-final appearances at six Australian Opens and Blake is yet to get beyond the fourth round in six attempts.