New York: Andy Roddick bid a tearful farewell to tennis after losing to Juan Martin del Potro in the fourth round of the U.S. Open on Wednesday, while Serena Williams and Novak Djokovic were all smiles after cruising into the next round. (Agencies)
Andy Murray and Maria Sharapova both dug themselves out of trouble to stay alive, and Italian Sara Errani booked a spot in the women's semi-finals by beating compatriot Roberta Vinci.
Roddick, the face of U.S. men's tennis for most of the past decade, was sent into retirement after losing 6-7 7-6 6-2 6-4 to Argentine del Potro.
"I've loved every minute of it," the 2003 U.S. Open champion told the crowd at Arthur Ashe Stadium. "It's been a road, a lot of ups, a lot of downs, a lot of great moments."
Djokovic was in complete control of his fourth round match against Stanislas Wawrinka, leading 6-4 6-1 3-1, when the Swiss called it quits in one of five matches that were held over from Tuesday because of rain.
"I really don't know exactly what it was but by the look of it, I think it was probably a dizziness or something," said Djokovic, the only man yet to drop a set in the tournament.
"He served well, he played well, but you could see that he didn't feel great on the court."
Sharapova needed all her fighting qualities to come from behind and beat Marion Bartoli of France 3-6 6-3 6-4 and reach the semi-finals at Flushing Meadows for the first time since she won in 2006.
Bartoli led 4-0 overnight and wrapped up the first set when play finally resumed after another morning shower but Sharapova regained her composure to win the next two and book a semi-final date with world number one Victoria Azarenka.
"It's so long since I've been back to this stage at the U.S. Open. A little bit of luck always helps," the Russian said.
American Williams, full of confidence and self-belief, demolished Serbia's Ana Ivanovic in less than an hour to show why is the overwhelming favourite to win the women's title for the fourth time.
"I feel like I'm going to get more focused and serious and start playing Serena tennis in the next couple of rounds, if I get to play two rounds. That's my goal," she said.
Williams will play Italian Errani in Friday's semis after she defeated doubles partner Vinci 6-2 6-4.
"A quarter-final with your best friend, of course, is difficult," said Errani. "We know each other very well, we've played together many times, so it was strange to see her on the other side of the net."
Olympic champion Murray produced an extraordinary turnaround to beat Croatia's Marin Cilic 3-6 7-6 6-2 6-0.
The Scot lost the opening set then fell 5-1 behind in the second with two service breaks before rallying back to win, reeling off the last 11 games in a row.
"It wasn't the best of starts," Murray said. "He got nervous towards the end of that (second) set once ... then I played a great match after that."
Serbia's Janko Tipsarevic beat German Philipp Kohlschreiber 6-3 7-6 6-2 and will face Spain's David Ferrer in Thursday's quarters.
Djokovic will face Del Potro, also on Thursday, while Murray plays either Roger Federer or Tomas Berdych in Saturday's semis.
New York: Andy Roddick bid a tearful farewell to tennis after losing to Juan Martin del Potro in the fourth round of the U.S. Open on Wednesday, while Serena Williams and Novak Djokovic were all smiles after cruising into the next round.