TOKYO — U.S. tennis star Coco Gauff will no longer lead the U.S. tennis team at the Tokyo Olympics. She has announced that she tested positive for the coronavirus, dashing her hopes of competing in the Games.

"It has always been a dream of mine to represent the USA at the Olympics, and I hope there will be many more chances for me to make this come true in the future," the 17-year-old said in a statement on her Twitter account.

Gauff was tapped to lead the 12-member group earlier this month, in what will be the first Olympics team in a quarter century without Serena or Venus Williams. Team USA called it a "changing of the guard."

The U.S. Tennis Association said the "entire USA Tennis Olympic contingent is heartbroken for Coco."

"We wish her the best as she deals with this unfortunate situation and hope to see her back on the courts very soon," it added, and said it knew she'll be rooting for her teammates.

Jennifer Brady, Jessica Pegula and Alison Riske will compete for the U.S. in women's singles.

Gauff did not state whether she has been vaccinated. It's possible but less likely for vaccinated people to test positive for the coronavirus.

Thousands of athletes, coaches, officials and media are streaming into Tokyo. They go through rigorous coronavirus testing before departing from their home countries and comply with strict protocols upon arrival to maintain separation from the Japanese population and decrease risk of an outbreak.

Still, positive cases are starting to emerge in the Olympic bubble, including two athletes from the same team. Their positive tests on Sunday made them the first known cases of athletes to test positive in the Olympic village.

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