KOENIGSTEIN, Germany, June 8 - Striker Ronaldo missed Brazil training on Thursday afternoon due to a fever and sinus infection but will be fit for practice on Friday, a team doctor said.

"He had an infection of the upper aerial tracts and it's responded well to treatment," Serafim Borges told reporters.

"Any individual is subject to an infection. He had a fever but the solution was satisfactory. It's completely over and done with, the athlete has no more problem."

He added: "These variations of temperature put any person at risk to such illness and this could have contributed to this infection. He'll be back tomorrow afternoon."

Ronaldo, 29, whose season with Real Madrid was punctuated by a series of minor injuries, has just recovered from a bout of blisters.

He limped out of Sunday's 4-0 friendly against New Zealand in Geneva at halftime complaining of blisters after scoring the first goal.

On Tuesday, team doctor Jose Luis Runco said he had made a full recovery.

Brazil have already named their squad for the Croatia game with Ronaldo due to partner Adriano in attack.

His Real Madrid team mate Robinho would be the likely replacement if Ronaldo were unable to play. Japan and Australia complete the group.