American tennis star Coco Gauff will not be participating at the upcoming Tokyo Olympics. The 17-year-old announced Sunday on social media that she tested positive for COVID-19 and will not play in this summer's Olympic Games.

"I am so disappointed to share the news that I have tested positive for COVID and won't be able to play in the Olympic Games in Tokyo," Gauff wrote on Twitter. "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. I want to wish TEAM USA best of luck and a safe games for every Olympian and the entire Olympic family."

Gauff shocked the tennis world when she upset Venus Williams at Wimbledon in 2019 as a 15-year-old. She reached the quarterfinals of the French Open earlier this year.

COVID-19 is looming large over the Tokyo Olympics, which kick off later this week after being delayed by a year. The first confirmed case of COVID-19 was found at the Olympic Village over the weekend. Two players from the South Africa men's soccer team tested positive in Tokyo, becoming the first athletes to do so in the Olympic Village.

The opening ceremonies for the Tokyo Games are set for Friday.