Defending champion Serena Williams cruises into the fourth round at Wimbledon . The U.S. Open is a major tournament for both men and women but it has been dominated by American women. Third seed Caroline Wozniacki also progresses into last 16 of grass-court grand slam . Sharapova , the 2004 champion , continued her comeback from long-term injury with an error-strewn 7-5 6-3 win over Barbora Zahlavova Strycova of the Czech Republic . Italian 10th seed Flavia Pennetta and No . 14 Victoria Azarenka of Belarus crash out .
Defending champion Serena Williams cruises into the fourth round at Wimbledon . The U.S. Open is a major tournament for both men and women but it has been dominated by American women. Third seed Caroline Wozniacki also progresses into last 16 of grass-court grand slam . Italian 10th seed Flavia Pennetta and No . 14 Victoria Azarenka of Belarus crash out .