NEW YORK (AP) A look at Thursday's play at the $34.3 million U.S. Open tennis championships:
WEATHER: Sunny and mild. High of 77.
ATTENDANCE: Day: 22,997. Night: 23,771. Total: 46,768.
MEN'S RESULTS: Quarterfinals: No. 9 Stanislas Wawrinka reached a Grand Slam semifinal for the first time, beating defending champion Andy Murray in straight sets. In the night match, No. 1 Novak Djokovic beat No. 21 Mikhail Youzhny in four sets. Doubles: Bob and Mike Bryan had their run to a Grand Slam ended, losing their semifinal match to Leander Paes and Radek Stepanek. The Bryan brothers had won four straight Grand Slam titles, 28 straight matches in all, since losing in the 2012 Wimbledon semifinals. They also won an Olympic gold medal last year.
WOMEN'S RESULTS: Serena and Venus Williams defeated No. 1-seeded Sara Errani and Roberta Vinci to advance to Friday's semifinal against No. 5-seeded Andrea Hlavackova and Lucie Hradecka.
STAT OF THE DAY: Stanislas Wawrinka hit 45 winners to 15 for Andy Murray, and didn't face a break point.
QUOTE OF THE DAY: "If someone told me before the U.S. Open last year I would have been here as defending champion having won Wimbledon and Olympic gold, I would have taken that 100 percent. So I'm disappointed, but the year as a whole has been a good one." - Andy Murray
FRIDAY ON COURT: Women's Semifinals: No. 1 Serena Williams vs. No. 5 Li Na, No. 2 Victoria Azarenka vs. Flavia Pennetta.
FRIDAY ON TV (All Times EDT): CBS, 12:30-6 p.m.
ON THIS DATE (Sept. 6, 1975): Manuel Orantes lost the first two sets, was down 0-5 in the fourth set and saved five match points before beating Guillermo Vilas in five sets in their semifinal match.