Ukrainian Elina Svitolina celebrates defeating Serena Williams.
Ukrainian Elina Svitolina celebrates defeating Serena Williams.

RIO 2016: Serena, Stosur dumped out of singles

TENNIS: Reigning champion Serena Williams has been knocked out of the Rio Olympics singles by Ukrainian Elina Svitolina.

Svitolina got on top of the usually dominant Williams serve to win 6-4 6-3 in a huge upset.

At one point Williams served five double faults in the same game as she followed Novak Djokovic out of Rio after already losing for the first time at the Olympics with sister Venus in the doubles.

Sam Stosur's Olympic campaign is also over, with a straight sets defeat to Australian Open champion Angelique Kerber.

The German raced through the first set 6-0 in the third-round clash before the Aussie put up a fight in the second before losing it 7-5.

Stosur said she had not given up on the idea of competing in Tokyo in 2020 when she would be 36.

"I can't say I'm expecting to be in Tokyo but if I can, and I can still stay healthy and do what I'm doing then I don't see why not,” the world No.17 said.

"Obviously the first set really got away from me; I think four games were deuce but I wasn't able to make any inroads and I felt I was always playing catch-up.

"In the second I started to get myself into the match and that 5-4 game was huge but you can't have a game like that and then let them off again by losing serve especially when they're a quality player like she is.”Stosur will partner John Peers against fourth-seeded Indian combination Sania Mirza and Rohan Bopanna in the opening round of the mixed doubles.Favourite and defending champion Andy Murray continued his comfortable progress with a 6-3 6-1 over Argentina's Juan Monaco to reach the last 16.

Rafael Nadal, who has won Olympic gold, defeated Italy's unseeded Andrea Seppi in straight sets, 6-3 6-3.