Naomi Osaka's gold medal hopes over after shock defeat in Tokyo Olympics third round

Living up to expectations as the poster athlete of an Olympic Games can be tough to handle and Naomi Osaka admitted it "was a bit much" after she suffered a shock loss in the third round of the women's tennis singles on Tuesday.

Osaka, 23, has been the face of the Tokyo Olympics. Her image is plastered across billboards and buses in the Japanese capital and she had the "greatest honour" of lighting the Olympic torch at Friday's opening ceremony.

Returning from a seven-week mid-season hiatus for mental health reasons, Osaka dispelled concerns over her physical sharpness with dominant wins in the first two rounds. Hopes of gold were heightened when two of her biggest rivals, world No 1 Ashleigh Barty and third-ranked Aryna Sabalenka, both lost early.

However, there was to be no triumph in Tokyo for the four-time Grand Slam champion following a 6-1, 6-4 defeat to the Czech Republic's Marketa Vondrousova on Tuesday.

“I’m disappointed in every loss, but I feel like this one sucks more than the others,” Osaka said. “I definitely feel like there was a lot of pressure for this. I think it’s maybe because I haven’t played in the Olympics before and for the first year [it] was a bit much.”

Indeed, the nerves told during the first set as Osaka struggled with her usually reliable groundstrokes and she soon found herself 0-4 down. After holding off two break points to trail 0-5, Osaka got her first game on the board but it was too little too late to salvage the first set.

The world No 2 appeared invigorated at the start of the second set and broke Vondrousova in the first game. A hold then gave her a 2-0 lead. But Vondrousova fought back to level at 2-2 and after surviving two break points soon moved into a 4-3 lead.

Serving to stay in the match at 4-5, Osaka fended off two match points and had two game points to stay alive in the match, but some fine defence from Vondrousova earned the Czech a third opportunity to clinch victory, which she took when Osaka fired a crosscourt forehand wide.

While both players produced 22 winners, Osaka hit 32 unforced errors to Vondrousova’s 10. But it wasn’t simply an off day for Osaka; it was also an outstanding performance from Vondrousova.

“I also [beat] Simona [Halep] twice, but I think now she [Osaka] is the greatest,” Vondrousova, the world No 42, said. “The greatest in the game, and she was also the face of the Olympics so it was tough for her, I think, to play like this.”

Vondrousova will take on Spain's Paula Badosa in the quarter-finals after she defeated Nadia Podoroska of Argentina 6-2, 6-3.

The Tokyo Olympics marked the first tournament for Osaka since the start of June when she withdrew from the French Open following the first round. Her withdrawal in Paris came a day after she was fined $15,000 and threatened with expulsion from the tournament after deciding to shun mandatory media obligations - a decision she made to protect her mental health.

“I’ve taken long breaks before and I’ve managed to do well,” said Osaka, who initially did not comment after her loss, then came back out and met with a small group of reporters. “I’m not saying that I did bad right now, but I do know that my expectations were a lot higher.

“I feel like my attitude wasn’t that great because I don’t really know how to cope with that pressure, so that’s the best that I could have done in this situation.”

Vondrousova sympathised with Osaka, saying: “It’s tough for her also playing in Japan and in the Olympics. It’s so much pressure, I cannot imagine.”

Osaka's exit, following those of Barty and Sabalenka, has further opened up the women's draw and any of the eight players in the quarter-finals will have ambitions of landing the gold.

Anastasia Pavlyuchenkova, representing the Russian Olympic Committee, continued her fine form in Tokyo with a 6-1, 6-3 win over Spain's Sara Sorribes Tormo. The 13th seed will meet Switzerland's Belinda Bencic in the quarter-finals after she fought back to defeat French Open champion Barbora Krejcikova 1-6, 6-2, 6-3.

Ukraine's fourth seed Elina Svitolina takes on Camila Giorgi of Italy, while Spanish seventh seed Garbine Muguruza will play Kazakhstan's Elena Rybakina, seeded 15th.