The Selecao talisman had been a fitness doubt after sustaining a couple of niggles in extra time of their last-16 penalty-shootout win over Chile.
Brazil team doctor Jose Luiz Runco has admitted that the 22-year-old Barcelona star may sit out a couple of training sessions to allow knee and thigh problems extra recovery time, but insisted that they would not prevent his involvement in the all-South American clash on Friday.
Confederation spokesman Rodrigo Paiva told reporters: "The worst is the knee, it's what's hurting the most.
"He may be rested from practice if needed. He will be evaluated again, but Runco said fans don't have to worry because he's not a concern for the match."