Barcelona goalkeeper Claudio Bravo has damaged a calf muscle and is doubtful for Saturday's La Liga match at Atletico Madrid, the champions said on Tuesday.
If Bravo, a Chile international, is ruled out, coach Luis Enrique is likely to deploy Barca's German keeper, Marc-Andre ter Stegen, in his place.
Last season, Bravo played in La Liga and Ter Stegen, who has four caps for Germany, in the Champions League and King's Cup, as the Catalan side swept to a treble of titles.
"Analysis by FC Barcelona's medical staff has revealed that first-team goalkeeper Claudio Bravo has suffered a muscular injury to his left calf," Barca said on their website (www.fcbarcelona.es).
"He will be closely monitored over the coming days and his availability for this weekend's match at Atletico will be determined based on how the injury evolves," they added.
Barca and Atletico won their opening two matches of the season and are joint top on six points along with Celta Vigo and Eibar.
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO_Sports and on Facebook at AhramOnlineSports.)