July 27 (UPI) -- Team USA star Simone Biles withdrew from the women's team gymnastics competition after she completed the first rotation on the vault Tuesday in Tokyo, USA Gymnastics announced.
"Simone has withdrawn from the team final competition due to a medical issue," USA Gymnastics said in a statement. "She will be assessed daily to determine medical clearance for future competitions."
A Team USA coach told NBC broadcasters earlier Tuesday that Biles' withdrawal was "not injury related" and is a "mental issue she is having."
"Physically, I feel good, I'm in shape," Biles told Today on Tuesday after she withdrew. "Emotionally, that kind of varies on the time and moment. Coming here to the Olympics and being the head star isn't an easy feat, so we're just trying to take it one day at a time and we'll see."
Biles said she is going to take it "day by day," when asked if she will return to future competitions at the 2020 Summer Games.
Team USA, led by Grace McCallum, Jordan Chiles and Sunisa Lee, still won a silver medal in Tuesday's event. The Russian Olympic Committee took the gold, while Great Britain took the bronze.
Biles met with team doctors after her vault rotation. She then changed into her warm-up outfit and stood on the sideline as her teammates participated in additional rotations. The four-time gold medalist finished in last place on her first rotation of the vault, one of her best events.
Biles, widely regarded as the greatest gymnast in history, admitted she struggled through qualifications earlier at the Summer Games. She cited mental pressure she faces in an Instagram post Monday.
"I truly do feel like I have the weight of the world on my shoulders at times," Biles wrote. "I know I brush it off and make it seem like pressure doesn't affect me, but [expletive] sometimes it's hard."
Chiles replaced Biles in Tuesday's beam and uneven bars competitions. Women's gymnastics events continue Thursday in Tokyo. The women's all-around final airs at 6:50 a.m. EDT Thursday on Peacock.