Andre Agassi's [Images] glittering career came to a tearful conclusion when he lost in four sets to German qualifier Benjamin Becker in the US Open third round on Sunday.

Becker, the world number 112 who is playing just his second grand slam event, sent the 36-year-old Agassi into retirement with a 7-5, 6-7, 6-4, 7-5 victory at Arthur Ashe Stadium.

Agassi, struggling with a chronic back injury that severely limited his mobility, did not have the physical strength to battle the hard-hitting German and at times yelped from the pain.

"You have given me your shoulders to stand on to reach for my dreams, dreams I could never have reached without you," the American told the crowd after sobbing for several minutes.

"Over the last 21 years, I have found you, and I will take you and the memory of you with me for the rest of my life."

Several seeded players were knocked out on the final day of the first week, including Argentine number four David Nalbandian on the men's side and Russian number five Nadia Petrova on the women's.

Former champion Lindsay Davenport [Images] saved two match points before beating Slovenian Katarina Srebotnik to join women's top seed Amelie Mauresmo in the next round. On the men's side, number two seed Rafael Nadal [Images], number nine Andy Roddick [Images], 15th seed Lleyton Hewitt [Images] and number 17 Andy Murray all advanced.

But all eyes were on Agassi, who had announced at Wimbledon that the Open would be the final tournament of his remarkable career.

Former champion Lindsay Davenport saved two match points as she squeezed past Slovenian 22nd seed Katarina Srebotnik, winning 3-6, 6-3, 7-6 to reach the fourth round.

The American 10th seed was well below her best but after saving the match points in the 12th game of the third set, snatched the tiebreak to clinch victory in just under two hours.

Agassi fought gamely but ultimately lost to the 25-year-old Becker, who fired 27 aces and 82 winners. After the match, Agassi sat on his courtside chair and cried with his head in his hands.

BACK PAIN

Agassi needed several cortisone injections over the last week to deal with his back pain. After a stirring five-set triumph over Marcos Baghdatis on Friday, he was in no shape for a repeat performance.

The sold-out crowd cheered wildly for Agassi but the eight-times grand slam winner could not move effectively enough to handle Becker's big shots.

"After my second-round match against Baghdatis, that was the worst I've ever been," Agassi said. "I just credit the doctors that I was able to get out there today. It's been such a day-by-day battle."

Becker, who faces Roddick in the fourth round, said he was determined to stay focused despite the crowd noise.

"In the fourth set, it was really loud," said Becker. "You can't be that loud. I got goosebumps right before I started serving.

"It was an unbelievable feeling walking out, feeling that kind of support, even though it was for him, how the crowd was into it. Yeah, that was a lot of fun."

Nalbandian lost his second-round match to former US Open champion Marat Safin [Images] 6-3, 7-5, 2-6, 3-6, 7-6 in a three-hour, 52-minute marathon, while Petrova was sent packing 7-5, 6-7, 6-3 by France's [Images] Tatiana Golovin [Images].

With new coach Jimmy Connors cheering him on, Roddick went the distance to subdue big-hitting Fernando Verdasco of Spain, 6-7, 6-3, 6-4, 6-7, 6-2.

"I feel like I got the best of Verdasco today," said the 2003 Open champion. "I thought he showed his best stuff. And so that makes it especially satisfying. I just tried to fight the whole way, and was fortunate today."

Davenport played well below her best but still finds herself in the fourth round after her 3-6, 6-3, 7-6 victory over Srebotnik. The American 10th seed won the decisive tiebreaker 7-5 after saving a pair of match points in the 12th game of the third set.

"At the end, I was trying so hard to play better and better, probably trying too hard," she said.

Unseeded former champion Serena Williams [Images] also advanced to the fourth round with a 6-2 6-4 victory over 16th seed Ana Ivanovic of Serbia and Montenegro.  

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