Russia's Elena Dementieva returns a ball to US Serena Williams during their semi final match on Day 10 at the 2009 Wimbledon tennis championships at the All England Club on July 2, 2012. Caroline Wozniacki of Denmark volleys against Edina Gallovitis of Romania at the Sony Erricsson WTA Tour's Pilot Pen Tennis on August 25, 2009 in New Haven, Connecticut. Kim Clijsters of Belgium celebrates