Bad news for Javier Mascherano. Tests on Wednesday confirmed that the Argentine player has a hamstring injury.
A statement released by Barcelona did not specify how long he will be out of action, just that his return will depend on how his recovery progresses.
However, he could be facing a minimum of two weeks out of action.
"The FC Barcelona medical staff have confirmed after tests carried out on Javier Mascherano that the first team player has an left thigh injury," the statement read.
"His return to action will depend on his recovery."
"The Argentine came on in the 62nd minute of the game against Atlético at Camp Nou in place of Denis Suárez. Mascherano managed to finish the game but he was in some discomfort at the final whistle.
"The versatile Mascherano has played 26 games this season, 15 in the league, four in the Copa del Rey , five in the Champions League and two in the Spanish Super Cup."
Luis Enrique will use Gerard Pique and Samuel Umtiti in Mascherano's absence, while he also has the option of Jeremy Mathieu.