A look at Monday's action in the final grand slam of the year
Italy's Roberta Vinci returns a shot to Poland's Agnieszka Radwanska in the fourth round of play at the 2012 US Open tennis tournament, Monday, Sept. 3, 2012, in New York. Vinci upset Radwanska 6-1 6-4.Henny Ray Abrams/The Associated Press
Tennis fans in Louis Armstrong Stadium during the U.S. Open tennis tournament in New York, Sept. 3, 2012.BEN SOLOMON/The New York Times
Martin Klizan, of Slovakia, during his men's fourth round singles match against Marin Cilic, of Croatia, in Arthur Ashe Stadium during the U.S. Open tennis tournament, in New York, Sept. 3, 2012. Cilic won 7-5, 6-4, 6-0.BEN SOLOMON/The New York Times
Tennis fans clamber for a tennis ball used during the men's singles match between Marin Cilic, of Croatia, and Martin Klizan, of Slovakia, in Arthur Ashe Stadium during the U.S. Open tennis tournament, in New York, Sept. 3, 2012. Cilic won 7-5, 6-4, 6-0.BEN SOLOMON/The New York Times
Martin Klizan of the of Slovakia hits a return to Marin Cilic of Croatia during their men's singles match at the U.S. Open tennis tournament in New York September 3, 2012. Cilic win 7-5, 6-4, 6-0.EDUARDO MUNOZ/Reuters
Marin Cilic of Croatia hits a return to Martin Klizan of Slovakia during their men's singles match at the U.S. Open tennis tournament in New York September 3, 2012.EDUARDO MUNOZ/Reuters
A tennis fan watches a match between Marin Cilic, of Croatia, and Slovakia's Martin Klizan as a child sleeps in his arms during the fourth round of play at the 2012 US Open tennis tournament, Monday, Sept. 3, 2012, in New York.Kathy Willens/The Associated Press
Angelique Kerber of Germany misses a shot against Sara Errani of Italy during their women's singles match at the U.S. Open tennis tournament in New York September 3, 2012. Errani won 7-6 (7/5), 6-3RAY STUBBLEBINE/Reuters
Serena Williams returns a shot to Czech Republic's Andrea Hlavackova in the fourth round of play at the 2012 US Open tennis tournament, Monday, Sept. 3, 2012, in New York. Willams won 6-0, 6-0.Julio Cortez/The Associated Press
Angelique Kerber of Germany celebrates a point against Sara Errani of Italy during their women's singles match at the U.S. Open tennis tournament in New York September 3, 2012.RAY STUBBLEBINE/Reuters
Ana Ivanovic, of Serbia, competes against Tsvetana Pironkova, of Bulgaria, during their fourth round women's singles match in Arthur Ashe Stadium at the U.S. Open tennis tournament in New York, Sept. 3, 2012. Ivanovic won 6-0, 6-4.BEN SOLOMON/The New York Times
Serbia's Ana Ivanovic returns a shot to Bulgaria's Tsvetana Pironkova in the fourth round of play at the 2012 US Open tennis tournament, Monday, Sept. 3, 2012, in New York. Ivanovic won the match.Kathy Willens/The Associated Press
Tomas Berdych of the Czech Republic celebrates after defeating Nicolas Almagro of Spain 6-4, 6-1 in their men's singles match at the U.S. Open tennis tournament in New York September 3, 2012.RAY STUBBLEBINE/Reuters
Andy Murray, of Britain, reacts after breaking the serve of Milos Raonic, of Canada 6-4 6-4 6-2, during a match at the U.S. Open tennis tournament, Monday, Sept. 3, 2012, in New York.Darron Cummings/The Associated Press
Venus Williams, left, and Serena Williams wave as they walk off the court following their 6-1, 6-4 loss to Russia's Maria Kirilenko and Nadia Petrova in their match during the third round of women's doubles play at the U.S. Open tennis tournament, Monday, Sept. 3, 2012, in New York.Charles Krupa/The Associated Press
Milos Raonic of Canada stretches to hit a return to Andy Murray of Britain during their match at the US Open men's singles tennis tournament in New York, September 3, 2012.ADAM HUNGER/Reuters