Serena starts women's U.S. Open defense

Williams, second seed and three-time champion, posted a 6-4, 6-1 win over fellow American Alexa Glatch as she seeks her third Grand Slam title of 2009. She won the Australian Open, was a quarterfinalist at the French Open, and beat sister Venus in the final at Wimbledon.

Former U.S. Open champion Kim Clijsters, 26-year-old Belgian, defeated Ukraine's Viktoriya Kutuzova with a 6-1, 6-1 rout in just 54 minutes. Clijsters earned her lone Grand Slam title at the 2005 U.S. Open. She returned to competitive tennis this month after taking two years off to get married and have a child.

Russia's Vera Zvonareva beat past Spain's Nuria Llagostera Vives, 6-0, 6-4; Victoria Azarenka of Belarus won 6-1, 6-1 over Romania's Alexandra Dulgheru; Italy's Flavia Pennetta beat Romania's Edina Gallovits 6-0, 6-4; and Frenchwoman Marion Radwanska beat Austria's Patricia Mayr 6-1, 6-2.

Copyright 2009 by United Press International.