Antoine Griezmann started for Barcelona as they beat Real Valladolid 1-0 on Saturday, but he had to be replaced at half-time, with Luis Suarez coming on to partner Lionel Messi up front.
Quique Setien confirmed after the game that the 29-year-old forward had asked to come off because he was feeling some discomfort after the first half.
The France international had to undergo scans on his right leg on Sunday which revealed he had suffered an injury and the Catalan side are unsure how long he will be kept out of action.
“Tests this morning have shown that first-team player Antoine Griezmann has a muscle injury in the quadriceps of his right leg,” a statement on the club’s website confirmed.
“He is therefore not available for selection at the present time and the evolution of the injury will condition his availability.”
Griezmann will at least be unavailable for Thursday’s match against Osasuna, but will likely miss the final clash with Deportivo Alaves on July 19.
The attacker’s injury will likely see Suarez return to the starting XI for the last two matches, as Setien confirmed on Saturday that he was just being rested after playing five games in a row.
The Catalan side are second in the Spanish top-flight and trail leaders Real Madrid by one point.