Brazil will begin their quest for a sixth World Cup trophy with no injury concerns, according to team doctor Jose Luiz Runco.
Roma right-back Maicon gave a scare when he went to ground clutching his lower back late in Brazil's 1-0 friendly victory over Serbia Friday, reported Xinhua.
But Brazil's medical staff have already cleared the 32-year-old of any serious damage.
"There was nothing in it, just a knock," Runco said.
"He is walking fine. All of our 23 players are fully fit for the first match (against Croatia June 12)."
Selecao boss Luiz Felipe Scolari has given his team the day off Saturday. The squad will resume training at their Granja Comary World Cup base, 100 km north of Rio de Janeiro, Sunday.
