Federer's most amazing stat: Durability

No stranger to jaw-dropping numbers, Roger Federer's most impressive statistic just might be one that doesn't involve hitting a tennis ball. Since he first appeared in a Grand Slam draw at the 1999 Australian Open, the world's best player hasn't missed a single one of tennis' major tournaments.

That's a span of 45 tournaments in 11 years. In a sport that beats up legs, knees, shoulders and minds like few others can, Federer has been a veritable Superman. Most of the rest of us pull a muscle playing for the company softball team. This guy circles the globe inflicting real punishment on his body and never misses a step.

And he's not showing up to these Slams with a limp, either. He has made 23 straight semifinals, an eye-popping stat that defies the laws of consistency in the sport.

Federer's amazing durability is something every other recent tennis star hasn't quite realized. Arch-nemesis Rafael Nadal has missed four Slams since playing his first in 2003. Pete Sampras missed five between 1990 and 1999. Andre Agassi missed 20 -- though most for reasons other than injury -- in the 20 years he competed. All of them have had their share of disappointing results.

We've worried before that Federer was losing his grip on dominance. When he lost to Nadal in 2009's Australian Open final, many writers -- this one included -- wondered if he would ever get to that record-setting 15th Slam title. When he lost to Juan Martin del Potro in last year's U.S. Open final, we were reminded of the coming generation of players that was closing the gap between Federer and the field.

At this year's Australian Open, injuries claimed almost all those would-be challengers. Nadal was forced to retire in the quarterfinals with a knee injury that will keep him out four weeks. Novak Djokovic -- who defeated Federer at the Australian Open in 2008 en route to his only Grand Slam win -- was slowed by breathing issues in a quarterfinal loss to Jo-Wilfried Tsonga. Del Potro was battling a wrist injury all tournament long. Andy Roddick -- who pushed Federer so admirably in last year's Wimbledon final -- hurt his shoulder in a quarterfinal loss to Marin Cilic. Even Murray -- who had looked like the most impressive player of the tournament headed into the final -- started feeling pain in his leg toward the end of that match.

In the end, only one man was left standing. In more ways than one.

"I always knew I had it in my hand. The question is do I have it in my mind and in my legs?'' Federer said after beating Murray. "That's something I had to work extremely hard at."

Federer now heads into the spring stretch with a world of confidence. Down a set and a break against Nikolay Davydenko in his quarterfinal match, Federer rebounded to play some of the best tennis we've ever seen from him, closing that set on a 5-0 run and then winning the rest of the eight sets he played in Melbourne. He's the undisputed No. 1 and talk is already bubbling about his chances at winning the calendar year Grand Slam.

Meanwhile, most of the rest of the top 10 is nursing injuries -- typical of the late months of the year, but a very troubling development for Feb. 1.

"Now I feel, like, obviously I'm being pushed a great deal by the new generation coming up," Federer said. "They've made me a better player, because I think this has been one of my finest performances in a long time, or maybe forever.''

His finest performance ever? That new generation had better get healthy ... fast.

Welcome back, Justine

She couldn't quite equal fellow Belgian Kim Clijsters' achievement of winning her first Grand Slam after coming back from retirement, but Henin accomplished something else nearly as important -- she presented a challenger for Serena Williams.

There hasn't truly been one since Henin left the game in May 2008. A few players have cycled through the top spot in the rankings since, but no one has been able to touch Serena when she's focused and at her best.

Henin may not have been ready to take down Serena in Melbourne -- her coach said as much -- but with a few more months of fine-tuning, she should be right back near the top of the rankings. Serena once again has motivation to stay sharp.

With Dinara Safina, Maria Sharapova, Ana Ivanovic and Jelena Jankovic -- all of whom took turns at No. 1 during Henin's absence -- struggling big time, we need someone to add depth at the top of the women's game.

The Associated Press contributed to this report.