RIO DE JANEIRO • An unpredictable Olympic tennis tournament claimed its biggest scalp of all, as Serena Williams crashed out in the third round of the women's singles.
The world No. 1's hopes of a fifth Olympic gold medal were crushed by Ukraine's Elina Svitolina on Tuesday, as she lost 6-4, 6-3 to an opponent 13 years her junior.
The top seed and defending champion, 34, was clearly struggling with a right-shoulder injury which had forced her to withdraw from the Rogers Cup in Montreal two weeks ago. At one point, she screamed in pain: "Shoulder, shoulder."
She even served five double faults in the seventh game of the second set, as she suffered her earliest-ever loss at an Olympic singles event. She also hit 37 unforced errors during the match.
"Obviously I am very disappointed. The better player won but I can't wait for next time. That will be a really good match and I look forward to it," said Williams.
"It was a great opportunity. It didn't work out the way I wanted it to, but at least I was able to make it to Rio. That was one of my goals."
SWITCH IN FOCUS
I tried not to think about playing Serena, the Olympic champion and (winner of) so many Grand Slams.
ELINA SVITOLINA, the young Ukraine tennis player who stunned top seed Serena Williams in the women's singles.
Svitolina - coached on the WTA Tour by one of Williams' former rivals, Justine Henin - broke for 5-4 in the opener and sealed it with an ace in the 10th game.
She was a break up again in the second set, nervelessly backing it up with a service hold for 3-1. Williams briefly rallied to break back at 3-3 but her calamitous seventh game sealed her fate.
"I didn't expect that I could win and I said don't think she will make a mistake. Just fight and focus," she said.
Svitolina added she was not surprised by Williams' uncharacteristic five double faults: "She can also hit four aces in a row, so I expected the unexpected.
"I tried not to think about playing Serena, the Olympic champion and (winner of) so many Grand Slams. I also thought she may be injured but I tried not to think about it too much."
Defeat means that the Rio tennis tournament has lost both its No. 1 players before the quarter-finals, after men's top seed Novak Djokovic went out in the first round.
Williams was joined at the exit on Tuesday by third seed and French Open champion Garbine Muguruza, who lost 1-6, 1-6 to Puerto Rico's Monica Puig.
Puig, 22, closed in on what would be only Puerto Rico's ninth Olympic medal and will face Germany's Laura Siegemund for a semi-final spot.
Muguruza refused to admit that she has found it tough to adjust to being a Grand Slam champion for the first time.
Her results since the French Open in June tell a different story.
Before arriving in Rio, she lost in the first round at Mallorca and Montreal and made just the second round at Wimbledon.
"I didn't find a way to beat her but I am over it. I have doubles and mixed (with Rafael Nadal) so I want to make sure I am not left with this bad taste," said the Spaniard.
Second seed Angelique Kerber eased past Australia's 2011 US Open winner Samantha Stosur 6-0, 7-5. She next faces British 10th seed Johanna Konta, who downed Svetlana Kuznetsova 3-6, 7-5, 7-5.
Things were much smoother for defending men's champion Andy Murray and 2008 winner Rafael Nadal, who coasted into the third round in straight sets.
Second seed Murray raced into the last 16, blitzing Juan Monaco of Argentina 6-3, 6-1.
Nadal, the third seed, was equally ruthless, claiming a seventh win in eight clashes against Italy's Andreas Seppi 6-3, 6-3.
REUTERS, AGENCE FRANCE-PRESSE, THE GUARDIAN