The club confirmed on Monday, potentially ruling out the striker for Wednesday’s Champions League tie against Bayern Munich.
The club have not put a timescale on Costa’s return to action, but local media reports suggest he will miss the next three weeks, starting with the visit to face the European champions in Munich.
“Diego Costa had to be replaced in the second half of our side’s game against Celta Vigo. Costa underwent tests at the Clinica Universidad de Navarra that confirmed he has suffered a muscle injury in the left thigh,” an Atletico Madrid statement said, adding that they are awaiting his response to treatment.
Atletico manager Diego Simeone is also likely to be without midfielder Saul Niguez and defender Jose Maria Gimenez on Wednesday. Both players missed Saturday’s 2-0 victory at Celta Vigo.