Tokyo Olympics 2020: Tennis star Naomi Osaka crashes out of Games in big upset

Japan's Naomi Osaka suffered a 6-1, 6-4 defeat to Marketa Vondrousova in the third round of the Tokyo Games, crushing her dreams of winning Olympic gold at home.

Osaka, chosen to light the Olympic cauldron during the opening ceremony, struggled in an error-strewn display under the centre court roof at Ariake Tennis Park and was knocked out in 68 minutes.

She made a dreadful start by dropping serve in the opening game.

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The second seed was broken twice more as 2019 French Open runner-up Vondrousova raced away with the first set.

Osaka broke in the second set but relinquished the early advantage with a double fault that allowed Vondrousova to level at two games apiece.

The world number two Naomi Osaka is out of the Olympics. Photo / AP

The four-time Grand Slam winner grappled with inconsistency, and even when given a sniff of regaining the initiative she had no response to Vondrousova's array of crafty drop shots.

Osaka saved two match points as she served to stay alive at 4-5 but Vondrousova converted at the third time of asking as the Japanese star smacked a backhand wide.

Vondrousova, ranked 42nd, will go on to face Spain's Paula Badosa or Nadia Podoroska of Argentina.