Atletico Madrid striker Diego Costa has sustained damage to his left hamstring, the club have confirmed.
The Spain international was substituted 69 minutes into his side's 3-1 Champions League win over Club Brugge at the Wanda Metropolitano on Wednesday.
Costa was sent for an MRI scan on Friday that showed he has a problem with his hamstring.
Atletico did not speculate on how long he will need to recover.
The former Chelsea forward netted twice in the UEFA Super Cup win over Real Madrid in August and once in the Champions League victory over Monaco last month, but has struggled for form in La Liga.
Costa has failed to score in any of his seven league matches this term and his last goal in the top flight was back in February, in the 5-2 defeat of Sevilla.
Atletico face Real Betis on Sunday in their final match before the international break.
Costa had already been left out of the Spain squad by Luis Enrique.
