Roger Federer can see the next generation of young rivals quickly approaching but the world's top player is not ready to hand over his Grand Slam supremacy just yet.
The 26-year-old Swiss star, who seeks his 12th Grand Slam title at the US Open, said Saturday that he can feel a host of younger foes closing upon him - and that doesn't even count French Open nemesis Rafael Nadal.
"He has already been up there too long. He's a veteran," Federer said of the second-ranked Spanish 21-year-old who won he third Roland Garros title in a row in June and pushed Federer to an epic five-set final at Wimbledon.
Federer's worries come from 20-year-old Serbian world number three Novak Djokovic, British 20-year-old Andy Murray, 21-year-old Czech Tomas Berdych, 21-year-old Frenchman Richard Gasquet and 22-year-old Cypriot Marcos Baghdatis.
"The new generation have announced themsevles since a year basically," Federer said. "One year ago they were still very young, not just young. But they are all very good.
"It's going to be interesting to see how well they can do at the Grand Slams."
Djokovic defeated Federer, Nadal and then Andy Roddick on the way to the Montreal Masters crown earlier this month while Gasquet made a Wimbledon semi-final run before falling to the world number one. "You could definitely tell one of them was going to make the breakthrough soon. It was Djokovic that did it first, even though it looked like Murray was going to do it ahead of him. He had problems with his injuries," Federer said.
"Gasquet has been able to make a breakthrough as well, making the semis at Wimbledon. You've always got Berdych, Baghdatis - all these other guys who can make the big breakthrough as well."
With Federer only three Slam titles shy of matching Pete Sampras for the all-time record, any rise and run by a new star would put his record bid at greater risk. Federer won his 50th career title earlier this month at Cincinnati and has captured 11 of the last 13 non-clay Slams.
"I'm in great shape. I've had the best summer of my life. Hopefully I can repeat the win at the US Open again," Federer said.
His win in a points race at North American tune-ups for the Open would net him a huge bonus and a 2.4 million-dollar total prize if he wins the Open. "It's a big purse, the biggest one in tennis," Federer said. "But you only get it if you win it. So it's a long way away."
Nadal hopes to keep that prize out of Federer's hands and take his Slam titles beyond feats of clay.
"I played a very good tournament in Wimbledon. I improved myself this year. I played the best season of my career," Nadal said. "I'm here practising hard. I've had good preparation for this tournament. I think that can help."