Andy Roddick announced his retirement on his 30th birthday. Reuters

Andy Roddick officially retired from tennis with a fourth-round loss to Juan Martin del Potro on Wednesday at the 2012 U.S. Open.

Roddick was in good shape heading into the second-set tie-breaker, but del Potro would eventually take control of the match with quality shots and steady play, 6-7, 7-6, 6-2, 6-4.

The crowd at Flushing Meadows were firmly behind Roddick, but the 2003 U.S. Open champion failed to muster enough against the seventh seed. While Roddick hit more aces (20) and more winners (57), the American also hit more unforced errors, and double faults than del Potro.

With his wife Brooklyn Decker in tears in the stands, Roddick addressed the fans with emotion in his voice.

"For the first time in my career, I'm not sure what to say," said Roddick, following the match.

"I know I have certainly not made it easy for you at times." he said with a laugh.

He fondly described his time as a player and a fan.

"I've loved every minute of it," Roddick said.

"One thing I am not scared of, is the people I go home to. They're great."

Roddick finished his speech by remembering his agent Ken Meyerson who died in October 2011.

The 30-year-old has had a prolific career. Roddick was at one point ranked No. 1 in the world, and went to three Wimbledon finals. The 2009 Wimbledon title match was among the most thrilling matches in history, as Roddick lost to Roger Federer in a five-set match that ended 16-14 in the fifth.

Del Potro moves on to play second-seed Novak Djokovic in the quarterfinals.