Brazil striker Ronaldo could miss Wednesday's World Cup semi-final because of an injury to his left thigh, said team doctor Jose Luis Runco on Saturday.
"At times these injuries take longer than you expect. If it doesn't improve with treatment then he will not be released for the game on Wednesday," he said.
"He is still a doubt. Just time will tell but he hasn't got a serious injury." Ronaldo was substituted in the second half of the 1-0 quarter-final defeat of England.
Runco said the injury had nothing to do with any of the knee injuries that had disrupted his career for the past two years.
"Since March 9 we have said that Ronaldo is in the same state as any other athlete. This is a common (injury) problem which could affect any other footballer."
He will have physiotherapy on Sunday and do light running in the afternoon, but no training with the ball.
"Normally in 72 hours the problem will clear up," Runco said. "I believe we have time to get him better by Wednesday and even more so by Sunday." The World Cup final takes place on Sunday in Yokohama.