Champions and former champions know the drill: Revolution always is in the air and nobody rules for too long. At 29, Roger Federer hasn't exactly been thrown on the scrap heap of tennis contenders, but he was reminded again Saturday of the natural order working against him.
That Federer lost a taxing five-set U.S. Open semifinal to Novak Djokovic, a man he had beaten three straight years at Flushing Meadows, must be considered an upset based on history and ranking. Federer entered the match No. 2 in the world, Djokovic No. 3; Federer has won a record 16 major tournaments, Djokovic one.
But the odds against Federer fending off younger challengers to his kingdom dwindle inexorably with time. Djokovic is only 23; his opponent in today's Open championship final (and the current No. 1), Rafael Nadal, is 24. And right behind them, Andy Murray, this year's Australian Open runner-up, is 23; this year's Wimbledon runner-up, Tomas Berdych, is 24. Robin Soderling, who knocked off Federer and Nadal the past two years on his way to successive French Open finals, is 26.
"It's normal," Federer said. "You can't go through a 10-, 15-year career thinking you'll always be at the very top. I think I did incredible work staying so long in the top two in the world. It's just not as easy as it seems. You can see with other players who are trying it. There are many tough guys out there, and it's gotten very physical, very mental."
Federer's lofty status hardly is diminished by a ghastly 66 unforced errors against Djokovic or the fact that his prized forehand - so long considered the best in the game - misfired repeatedly in the fifth set. As Federer noted, a match "won't be decided on winners only. You can also see mistakes, and [Djokovic] pushed me to make those. Credit to him."
But for a fellow who hadn't appeared capable of cracking on the biggest points - against a man who has - Federer suffers mostly from comparisons to his past self. Juxtaposed to his 23 consecutive advances to major singles semifinals ended at last year's French, Federer's current streak - quarterfinal exits from the French and Wimbledon before Saturday's U.S. semifinal loss - pales drastically.
To Djokovic, Federer still has experienced only "a minority of matches that he has lost comparing to the matches he has won in those situations. I mean, come on - 16, 17, I don't know how many majors. He definitely has been still playing well when he needed to."
On a daily basis through the two-week Open, questions raged over whether Federer's Grand Slam-winning days are over, and whether Nadal is destined to replace Federer as the sport's standard of excellence.
"Sorry if I cannot answer really well," Djokovic said. "But, you know, stats and results tell you everything. Roger results-wise is the best ever. Then you have Rafa, who has won Davis Cup and Olympic gold medal and all these things and still very young and still having a lot of time to come."
Federer acknowledges the changing landscape. "But I think I'm doing really well under the circumstances with as many challengers," he said. "I got a few guys back who were able to beat me, and many times when I lose, I feel like it's on my racket.
"That's a good thing, you know. I wouldn't want to feel that I couldn't compete with the new generation, but I can. It's not a problem for me."
If it isn't now, of course, it will be. Happens to the best of them.