Costa injured his thigh in Brazil's 2-0 win over Costa Rica on June 22. He has already missed Brazil's last group-stage game on Wednesday and the team's round of 16 encounter.

"Good news. Douglas Costa is back to training with the rest of the squad and participated in today's training session," CBF said via their official Twitter account.

Brazil will face Belgium in the quarter-finals in Kazan on Saturday morning (AEST).