Stefan Savic suffered a grade two hamstring tear in Atletico Madrid's LaLiga win against Levante, the club have announced.
Savic was replaced in the ninth minute of Sunday's 1-0 victory, which was sealed by a penalty scored by Antoine Griezmann.
The three points came at a cost, though, as Savic - who has started 12 LaLiga games this term - is set for a spell on the sidelines.
Atletico offered no timescale for Savic's recovery but he is likely to be out of action for around three to four weeks.
Savic joins Filipe Luis on the sidelines for Atletico with right-sided defender Juanfran having to fill in at left-back against Levante.
Lucas Hernandez, a transfer target for Bundesliga champions Bayern Munich, is back in training after more than a month out with a knee strain.
Manchester United report: Antony's future has already been decided after new comments from CEO
‘Slot hasn’t come in and changed everything, making it all about himself – it’s been about the players he’s inherited, getting the best out of a system he likes’: Liverpool manager impressing former players with personality and tactical approach
