Gymnastics superstar Simone Biles has withdrawn from the uneven bars and vault finals at the Tokyo Olympics, Team USA said Saturday.

Biles, however, remains eligible to compete in the finals for the floor exercise Monday and the balance beam Tuesday.

"She will continue to be evaluated daily to determine whether to compete in the finals for floor exercise and balance beam," the team said in a statement.

U.S. gymnast MyKayla Skinner, who had the fourth-highest score on vault during qualifying, will take Biles' place in the vault final.

It is the latest unexpected turn in an Olympic Games that was supposed to be a showcase for Biles and which has thrust the four-time gold medalist headlong into the conversation about mental health and athletics.

Biles, who came into the Games as the heavy favorite, has cited her mental health as the reason for withdrawing from the competitions.

"For anyone saying I quit, I didn't quit, my mind and body are simply not in sync as you can see here," Biles wrote Friday in an Instagram post. "I don't think you realize how dangerous this is on hard/competition surface. Nor do I have to explain why I put health first. Physical health is mental health."

Biles added that she was still suffering with "the twisties" and "literally can not tell up from down."

Biles pulled out of the individual all-around competition after shocking the Olympic world Tuesday by suddenly withdrawing during the team gymnastics final.

Since then, Biles has received widespread support from other athletes, including U.S. Olympic swimming legend Michael Phelps, who has been open about his battle with depression.

"We remain in awe of Simone, who continues to handle this situation with courage and grace, and all of the athletes who have stepped up during these unexpected circumstances," Team USA said in the statement issued Friday night ET.

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