Barca went back to the top of La Liga with a convincing victory, but the Brazil international was brought off as a precaution after injuring his ankle.
"He hurt the ankle he had injured previously, so we decided to take him off," he told AS after the game.
"All the forwards have to work and combine and find spaces. This season has just started. There will be a lot of [changes] in the table."
Barca have won all four games this season.