Gymnastics superstar Simone Biles has withdrawn from Thursday's all-around at the Tokyo Olympics.

The American had withdrawn from the team competition on Tuesday, saying she suffered from psychological problems. 

Gymnastics superstar Simone Biles, who surprised Tuesday by retiring in the Tokyo Olympics team competition, is forfeited Thursday's all-around.

The American had confided to suffering from psychological problems, saying "having to deal with demons in (s) a head". 

"After a medical evaluation, Simone Biles withdrew from the all-around final" which is held on Thursday, the American Gymnastics Federation said on its Twitter account.

She is still qualified for four finals to be held the following week.