Japan's Naomi Osaka is out of the Tokyo Olympics after losing on Tuesday in straight sets to Marketa Vondrousova of the Czech Republic in the third round.The loss is a major upset and a shock to the host country. Osaka is considered the face of these Games and lit the cauldron during the Olympic opening ceremony a few days ago. Osaka had played well in the tournament's first and second rounds but struggled against Vondrousova in the third round. Vondrousova beat Osaka 6-1, 6-4. The Japanese star had 32 unforced errors and won only 49% of her points when serving.Osaka came to the Olympics refreshed and happy, in her words, after a difficult couple of months. She withdrew from the French Open after announcing she wouldn't participate in press conferences. Osaka revealed she'd been dealing with depression and anxiety and also decided to skip Wimbledon.The top two women's tennis players have now lost at the Olympics. Top-ranked Ash Barty of Australia lost in straight sets in the tournament opener. Copyright 2021 NPR. To see more, visit https://www.npr.org.