Injured Sandro out of Copa America
Scans revealed that the Tottenham Hotspur player, who missed Brazil's Group B draws against Venezuela and Paraguay, has a calf muscle strain and a ruptured knee cartilage.
"Due to this and because there won't be enough time for the player's recovery at the Copa America, the coaching staff opted to send the player home," the CBF said in a statement on its website.
Sandro, 22, was leaving for Sao Paulo on Tuesday to then travel on to London for more tests at his club. Coach Mano Menezes is not allowed call up a replacement.
Brazil were travelling from their base outside Buenos Aires to Cordoba on Tuesday for their last Group B match against Ecuador on Wednesday when they will looking to qualify for the quarter-finals.
Holders Brazil are second equal in the group with Paraguay, both two points behind leaders Venezuela. Ecuador are bottom with one point.