Roger Federer turns 30 this year. How much does he have left?

Thirty, it's an age at which other athletes are entering their primes, but for tennis players has historically marked the beginning of the end. Pete Sampras only won one Grand Slam after hitting the big 3-0. Bjorn Borg, Ivan Lendl, John McEnroe, Boris Becker, Mats Wilander and Stefan Edberg had none. Jimmy Connors and Andre Agassi managed to add two Slams each after entering their fourth decades, but they're the outliers in the modern era.

So when Roger Federer turns 30 on Aug. 8, history dictates that his days of winning Grand Slams will largely be finished. The past tells us he will still contend, and perhaps even win one or two, but that he won't be a consistent threat to win every time he steps onto the court.

Don't bury him yet, though. History also said that no one could win more than 14 Grand Slams and that 10 major semifinals in a row was the pinnacle of consistency in the majors. Federer extended those marks to 16 and 23, respectively. If Federer doesn't win many more Slams, it won't be because of some arbitrary line of aging demaraction. We're supposed to believe you decline at the precise moment you reach 10,950 days old? Why not at 29 years or 31 years or 245 months? Just because Borg retired at 25 or because Pete Sampras only relied on his serve late in his career, Federer can't have a few more good years in him?

Of course he can. He's a different animal. The same old rules for his tennis twilight don't apply. The addition of Paul Annacone has invigorated the game of the 16-time Grand Slam champion. He looks like his old athletic self on the court, taking control of points rather than passively waiting for his opponent's to make mistakes and varying his play as the situation warrants. Federer knows that his talent can't get him out of binds like it used to. If he wants to contend, he'll have to be more cunning than he's been in the past.

And contend he will. Provided he stays healthy, Federer will be a threat to win in Melbourne, Wimbledon and New York this year and in the near future. He's won 22 of his last 23 matches and is 36-3 since mid-August. His unbelievable semifinal streak was stopped last year and he had that disappointing loss in the US Open semis after holding match point, but you could argue Federer ended 2010 playing some of his best tennis in years.

If you gave him some truth serum, I think Federer would tell you he had two goals: to get to 20 Slams and/or to put the record out of reach for Nadal (who currently has nine). Given that Nadal is five years younger, Federer would have to get to 18 or 19 in order to feel comfortable with the latter. But, then again, Nadal is an old 24. His style of play has led to recurring knee issues and it's possible injuries may keep him from even getting to the 16 Slams Federer has now. Or Nadal could win the Grand Slam this year and begin 2012 just three away.

We don't know. And that's what makes the thing it so darned interesting. 

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