Andy Roddick announced last week he would end his tennis career at the 2012 U.S. Open, and Juan Martin del Potro sent the American packing in a fourth-round affair Wednesday at the USTA Billie Jean King National Tennis Center.

Also on Wednesday, sixth-seeded Tomas Berdych ousted top-seeded Roger Federer, 7-6 (7-1), 6-4, 3-6, 6-3 in the quarterfinals.

The seventh-seeded del Potro came from behind to beat the 20th-seeded Roddick 6-7 (1-7), 7-6 (7-4), 6-2, 6-4 at Arthur Ashe Stadium in a match that was suspended because of rain on Tuesday night.

Roddick snuck out a first-set tiebreak against del Potro, but the towering Argentine rebounded by taking a second-set tiebreak, which appeared to take a lot of energy out of the outgoing American slugger.

It was all del Potro in the third set and that momentum carried over into the fourth, as the Argentine ultimately cruised to victory at the world's largest tennis stadium.

The match was over in 3 hours, 15 minutes, as the big-serving Roddick swatted 20 aces in his final outing, but had his serve broken four times, compared to only one break by the American.

The 23-year-old del Potro improved to 4-1 lifetime against Roddick.

The former world No. 1 Roddick captured his lone Grand Slam title at the 2003 U.S. Open and was the 2006 runner-up to Roger Federer in New York. Roddick also succumbed to Federer in three Wimbledon finals, including their epic five-set battle at the All England Club in 2009, when the Swiss finally prevailed in a 30-game fifth set.

The Nebraska native/Texas resident Roddick announced his impending retirement on the day of his 30th birthday last week.

Roddick, who failed to reach a major quarterfinal this year, ends his career with 32 titles in 52 finals and is the second-winningest American in Davis Cup singles history, behind only the legendary John McEnroe. Prior to Wednesday, Roddick was second only to Federer among active players in career match wins, with 612.

The crowd favorite Roddick went 43-12 in Flushing.

"For the first time in my career I'm not sure what to say," a tearful Roddick said on the court after falling to del Potro. "I've loved every minute of it."

"It's been a road with a lot of ups and a lot of downs," Roddick added. "I love you guys with all my heart."

Roddick went on to thank his family, including his mom and dad, and his support team.

The 6-foot-6 Del Potro stunned Federer in the final in Flushing three years ago, halting a 40-match U.S. Open win streak by the Swiss great.

The 2009 U.S. Open champion del Potro is rewarded with a quarterfinal bout against reigning champion and two-time U.S. Open runner-up Novak Djokovic, who was an easy winner on Day 10 of the Big Apple fortnight.

The second-seeded recent world No. 1 star Djokovic won his 11th straight match in Flushing with a 6-4, 6-1, 3-1 spanking of 18th-seeded Swiss Stanislas Wawrinka, who appeared ill and decided to retire in the third set. The match was suspended by rain Tuesday night, with the formidable Serb leading 2-0 in the first set. Rain also disrupted play on Wednesday.

The 25-year-old Djokovic got past Wawrinka in 1 hour, 33 minutes.

The five-time Grand Slam champion Djokovic captured his first U.S. Open title last year by handling former winner Rafael Nadal in a 1-versus-2 finale at the National Tennis Center. The Serb also stopped the Spaniard in this year's epic Australian Open finale, while Nadal beat Djokovic in the French Open final in June.

Third-seeded Andy Murray ousted Marin Cilic, the No. 12 seed, by a 3-6, 7-6 (7-4), 6-2, 6-0 margin.

After dropping the first set, the 2012 Wimbledon runner-up fell behind 2-5 in the second stanza, but rallied back to capture the final five points of the set after taking the tie breaker 7-4.

Murray, who was the runner-up at the U.S. Open in 2008, fired off 11 aces over the match, which lasted nearly three hours.

The 2012 Olympic Gold Medalist will face Berdych in the semifinals on Friday.

Berdych won 11 break points to take down the five-time U.S. Open titlist for the second consecutive matchup in a Grand Slam event. Berdych defeated Federer at Wimbledon in 2010 en route to his only Grand Slam final to date.

"I (couldn't) count on beating Roger in straight sets," said Berdych. "I was always careful that anything could happen."

Federer, the world No. 1, was denied his 33rd career Grand Slam semifinals appearance in the loss, but still leads the head-to-head record 11-5.

Also on Day 10 in New York, Djokovic's eighth-seeded fellow Serb Janko Tipsarevic dismissed 19th-seeded German Philipp Kohlschreiber 6-3, 7-6 (7-5), 6-2 to reach the U.S. Open round of eight for a second straight year. Tipsarevic-Kohlschreiber was also suspended because of rain on Tuesday, with the Serb leading 5-2 in the opening set.

Tipsarevic is rewarded with a quarterfinal match against fourth-seeded fellow grinder David Ferrer of Spain.