Serena Williams beats Jelena Jankovic to reach Cincinnati semis

World number one Serena Williams remains on track for a first Cincinnati title with victory over eighth seed Jelena Jankovic in the last eight.

The American won 6-1 6-3 to set up a semi-final against Agnieszka Radwanska or Caroline Wozniacki on Saturday.
World number two Simona Halep takes on Maria Sharapova in a rematch of the French Open final later on Friday.
Britain's Andy Murray faces third seed Roger Federer in the men's quarter-finals.
Federer's fellow Swiss, Stan Wawrinka, suffered a shock 1-6 6-1 6-2 defeat by Julien Benneteau earlier on Friday.
The Frenchman won 12 of the last 15 games to reach the first Masters semi-final of his career, where he was joined by Canadian fifth seed Milos Raonic, who crushed Italy's Fabio Fognini 6-1 6-0 in just 57 minutes.