The 29-year-old suffered the injury during a clash with Elche this summer.
It was expected the Brazilian would return to action after a month.
“Today’s (Thursday) training session has been the best one yet and little by little, I am gaining the confidence that I need to be able to play a game at a hundred percent,” he told Marca.
“It will be a bit difficult to make the Villarreal game. Even though I really want to play, I feel that it is a little too soon.”