World No . 1 Murray , meanwhile , might still be coming to terms with his epic victory at Wimbledon that ended Britain 's 77-year men 's singles drought , although Berdych improved to 6-4 against the Scot . Novak Djokovic will enter this year 's U.S. Open without a title since April . He loses to big - serving American John Isner at the Cincinnati Masters on grass . Andy Murray also exits in the quarterfinals after a defeat to Czech Tomas Berdych . Serena Williams reaches the semifinals by ousting Romania 's Simon Halep .
World No . 1 Novak Djokovic will enter this year 's U.S. Open without a title since April . He loses to big - serving American John Isner at the Cincinnati Masters on grass . Andy Murray also exits in the quarterfinals after a defeat to Czech Tomas Berdych . Serena Williams reaches the semifinals by ousting Romania 's Simon Halep .