Between them they and Agassi (1999) have captured six of the last seven US Open titles. The lone champion missing from that stretch is Pete Sampras (2002) who retired after his final US Open appearance.

Safin, who won six years ago in New York, continued his domination over David Nalbandian, upsetting the fourth seeded Argentine 6-3, 7-5, 2-6, 3-6, 7-6 in a second round match.

"Of course, everytime you come back after you have won it, you want to get closer to the final," Safin said.

"These days it is a different story. A lot of good players left and some others came in. The young ones are hungry and anybody can beat anybody. It is not as easy as it used to be."

No doubt Agassi -- bad back and all -- will second that. The eight time Grand Slam winner and two time US Open champ lost to unheralded Benjamin Becker of Germany 7-5, 6-7, 6-4, 7-5 to bring down the curtain on his career.

Andy Roddick, whose lone major title came in New York in 2003, reached the fourth round with a 6-7, 6-3, 6-4, 6-7, 6-2 victory over Fernando Verdasco of Spain.

Roddick will attempt to avenge Agassi's defeat when he faces Becker next for a place in the quarterfinals.

The 2001 champ Hewitt reached the fourth round with a 6-3, 6-1, 6-2 victory over world number 23 Novak Djokovic.

Two-time defending champion Federer crushed American Vince Spadea 6-3. 6-3, 6-0 in an evening match.

Federer will play unseeded Marc Gicquel of France for a place in the quarterfinals. Gicquel came through a tough five-setter against former French Open winner Gaston Gaudio of Argentina.

It was the Swiss star's 17th straight win at Flushing Meadows and moves him another step closer to becoming just the third man in the Open era after John McEnroe and Ivan Lendl to win a hat-trick of US Open titles.

"Three matches, three straight sets it couldn't be better," he said. "I'm looking forward to the next match now."

The unseeded Safin has booked a date with Olivier Rochus of Belgium for a place in the fourth round. Safin, who has 15 career singles titles, is currently ranked 104th in the world, his lowest ranking since 1998.

But the 26-year-old Russian continued his solid play as he comes back from a left knee injury and improved his career record against Nalbandian to 6-1.

"It feels good, especially beating good players like Nalbandian. Hopefully I can continue heading closer to the final," he said.

Safin, who won his first Grand Slam title here in 2000, fired 14 aces and hammered 53 winners in the 3hr, 46min five-set marathon.

Roddick was pleased to get through but said he was torn over the prospects of his next match which would have been against ailing Agassi had he gotten past Becker.

"You don't want to be the guy that shot Bambi," Roddick said.

After beating Verdasco, Roddick, who has seen his world ranking drop to No. 10, boasted Sunday that he would be a prime-time player again.

"I will be top five again, by the way," said the former world number one.

Hewitt, the 15th seed, will now face Richard Gasquet of France who beat Switzerland's Marco Chiudinelli 7-6, 6-3, 2-6, 7-6.

Aussie Hewitt is nursing a sore knee in New York, but the injury isn't slowing him down.

"I am happy with the way I can compete out there at the moment," Hewitt said.

Former women's champ Lindsay Davenport survived her first real test of the US Open Sunday by digging deep to beat Slovenia's Katarina Srebotnik.

Davenport fought off two match points against world number 23 Srebotnik to win 3-6, 6-3, 7-6 and also reach the fourth round.

The 10th seed Davenport will next play seventh seed Patty Schnyder of Switzerland who also rallied to beat France's Marion Bartoli 0-6, 6-3, 6-3.

Also on the women's side, unseeded Serena Williams raced into the fourth round with a 6-2, 6-4 victory over 18-year-old Ana Ivanovic.

Williams will now play top seed Amelie Mauresmo of France who beat Italy's Mara Santangelo 6-3, 3-6, 6-2.

Williams goes into the match brimming with confidence knowing she has a 9-1 career won-loss record against Mauresmo.

"We always have some really matches. I like the way she hits the ball," Williams said.