MASON, OH (FOX19) - The Western & Southern Open delivered its first big upset of the tournament on Thursday when Tommy Robredo knocked out Novak Djokovic 7-6, 7-5, in the third round. Robredo, ranked number 16 in the world, took down the number one ranked player in the world with the win. Djokovic leaves Mason once again without a title after finishing as a runner-up in four previous trips.
Roger Federer took care of business under the lights on center court defeating Gael Monfils 6-4, 4-6, 6-3. It was Federer's 301st win in a Masters Tournament, the most all-time by any tennis player. Federer will go up against Andy Murray in a quarterfinal showdown Friday after Murray unseated John Isner in an epic three-set showdown, 6-7, 6-4, 7-6.
In women's third round action, Serena Williams and Maria Sharapova didn't waste any time disposing their opponents. Williams defeated Flavia Pennetta 6-2, 6-2. Williams is 12-0 on American hard courts this season, but is still in search of her first title at the Western & Southern Open. Williams will face Jelena Jankovic on Friday. Sharapova devoured Anastasia Pavlyuchenkova 6-4, 7-6. Sharapova will battle Simona Halep in Friday's quarterfinals.
Other notables moving on to the quarterfinals include Ana Ivanovic and Stanislav Wawrinka.