As the Australian Open begins in Melbourne this week, Roger Federer, the safest bet in sports, finds himself even more a favorite than usual.

Just as Federer pronounced his injured ankle 100% healthy last week, several of his chief rivals at the first major of 2006 collapsed in a heap. Gone from the draw are defending champion Marat Safin (knee), world no. 2 Rafael Nadal (foot), and four-time champion Andre Agassi (ankle). Better still for Federer (and worse for everyone else), the men who have the best chance of upsetting the world no. 1 – Argentina’s David Nalbandian, Croatia’s Ivan Ljubicic, and American Andy Roddick – are thrown together in the same half of the draw. As they wear one another out, Federer will have little to contend with, save the hometown favorite, Lleyton Hewitt, who has shown poor form early this season and has lost nine straight to the master.

There is, however, a formidable competitor in the world of tennis this year that Federer, great as he is, will need more than a little luck to defeat: History. Having finished seven plus seasons as a pro, the 24-year-old Swiss is, on paper, nearly indistinguishable from the best player the game has known, Pete Sampras. But can Federer maintain his pace or even surpass Sampras, most notably his record 14 Grand Slam titles?

A detailed look at these two careers suggests that Federer’s chances are average at best, though he could greatly help his cause by winning three majors in 2006, as he did in 2004.

The similarities between the two are remarkable. After playing little in their first seasons, Sampras and Federer over the next seven years won their matches at rates of .773 and .765, respectively. If one removes from the equation all matches played on carpet (more popular in Sampras’s better years and far less so during Federer’s) leaving only hard courts, clay, and grass, Sampras’s winning percentage at age 24 stands at .783, compared to .778 for Federer. Sampras had won 36 titles, including seven majors; Federer 33 and six.Sampras had finished no. 1 for three straight years (he later set the record at six), while Federer has finished on top the past two seasons.He lost by a smidgen to Roddick in 2003.

In many ways, Federer has proven superior, justifying his reputation, in the words of Agassi,as the most skilled player ever. His winning percentage against Top 10 players is .670, compared to Sampras’s .602 (from 1988-95). From 2003 through January of last year, Federer won 24 consecutive matches against Top 10 opponents, an absurd streak. While Sampras never finished a season with a winning percentage above .900, Federer has finished his last two years at .925 and .953. He won 11 titles in each of those years (Sampras never won more than 10), and his record in finals is better, too: .786 to .735.

Yet as phenomenal as Federer is, there are numerous reasons why one should not expect him to match or better Sampras.

The most obvious is that there is no margin for error or serious injury. During the final seven years of his career, Sampras was just as remarkable as he was in his first seven: He won another 28 titles, including seven majors, slightly improved his winning percentage (from .773 to .776), won slightly less often in finals (.718 from .735), and fared better against Top 10 players (.683 to .602). From 1997 to 2000, he won four straight Wimbledon titles, completing a stretch in which he won that title seven times in eight tries.

Even if Federer remains in excellent health (which history, not to mention Federer’s recent foot and ankle problems, suggest is unlikely), matching these feats will be extraordinarily difficult.He’ll have to win the bulk of his majors by the end of 2010, when he’ll be 29, as Sampras was in 2000 (Sampras won one major after age 30; Agassi, considered the best late-career player since Jimmy Connors, has won two and does not look likely to win more). By the end of 1997, Sampras had collected 10 major titles, which means Federer would have to win a total of four this season and next just to even the score.

To do this, Federer likely will have to continue producing remarkable performances in finals, where he wins slightly more often than he does overall (.786 to .778).Perhaps he will prove to be the best ever in important matches, but he’s unlikely to keep up this pace. Sampras lost four Grand Slam finals; Federer, who is 6-0, is bound to lose one along the way. Sampras’s winning percentage in finals was lower than his overall percentage by about .050, as one would expect against better opponents.

Federer’s style of play does not work in his favor, either.

No one will question that Federer’s game has far more depth than Sampras’s ever did.His forehand and backhand are superior,his footwork is better,his speed is better, his service return is better. He is by far the most complete player the game has ever seen, someone who could win all four majors (only the French Open, on clay, remains).

Yet versatility may not prove to be the best asset over the years. If Federer’s ankle woes and struggles with plantar fasciitis, a painful heel condition,continue,one would expect him to lose a step. All the beauty in Federer’s game begins with his remarkable feet; if they deteriorate, he’ll become more vulnerable in rallies, less fearsome on passing shots, and less explosive on return games.

Sampras, far less versatile, owned a weapon more powerful than any in the Federer arsenal: his serve. It’s still the most important stroke in tennis, and it’s also the one that holds up the best over time,as it requires no running and is not influenced by the opponent. Even as he aged and ached, Sampras remained a phenomenal server until the end. From the time the ATP Tour began tracking serving statistics in 1991, he held his service games 88.7% of the time,and he did even better in his last seven years (89.1%). If we toss aside serving statistics from Federer’s first three seasons, he holds serve at 87.4%.The difference is slight, but it could make a difference down the stretch if the rest of Federer’s game looses its polish.

Of course, luck may still be on Federer’s side. Maybe he will remain healthy until age 32 or even 33. Maybe, as frightening a thought as it is, he will improve, or win a few French Opens – a title that eluded Sampras. Maybe the rest of the men’s field will decline, or suffer from a rash of injuries in the next few years. Having drawn such a weak field in Australia, Federer has an opportunity he cannot afford to miss. If he wins this and another major in 2006, the race with Sampras is still on. Three, and he takes the lead. One, well, that might just put Sampras out of reach. Looking at all the facts, it is not sensible to argue that Federer will succeed. But as always, it seems foolish to bet against him.