Serena Williams on a tear going into US Open

Wimbledon champion Serena Williams is ranked fourth going into the U.S. Open but has to be considered the favorite to pick up a third title in New York. Williams won women's singles titles at the Open in 2001 and 2009 and she was the runner-up a year ago. That was when she was still on a comeback trail from a series of injuries that struck after she won at Wimbledon in 2010. Since an uncharacteristic first-round loss at the 2012 French Open, Williams is 19-1 with the Wimbledon win and a title at Stanford, Calif., followed by a dominating gold medal-winning performance at the Olympics in that string. She has 7,300 ranking points despite appearing in only 15 tournaments over the ranking period. Most players have more than 20 appearances. There was one slight change in the Top 10 as women's tennis starts its final Grand Slam event of the year Monday. Li Na edges past Carolina Wozniacki into eighth place, dropping Wozniacki to ninth. Victoria Azarenka remains No. 1 with 9,025 points while Agnieszka Radwanska is second at 8,115, with Maria Sharapova in third with 7,695 and Williams at No. 4. Petra Kvitova (6,415) is fifth after winning the title at New Haven, Conn., Saturday and Angelique Kerber (5,705) is at No. 6. Defending U.S. Open champion Samantha Stosur is seventh and has 5,700 points while Li has 4,371 and Wozniacki has 4,335. Sara Errani completes the Top 10 with 3,860. Last week's other WTA champion was Roberta Vinci, whose victory in Dallas Friday moves her from 23rd to 19th in the rankings.