Hansi Flick has been dealt a fresh blow ahead of next Sunday's Clasico against Real Madrid at the Camp Nou, in the tenth round of the Spanish league.
Dani Olmo limped off during Barcelona's defeat to Paris Saint-Germain on Tuesday in the Champions League, which the French side won 4-2.
Spanish newspaper "AS" report that Olmo left the Parc des Princes pitch frustrated, clutching his thigh in worrying fashion after being replaced by Fermin Lopez in the 27th minute.
Initial reports point to a tear in Olmo's left thigh muscle. It's a serious injury that will rule him out of the Clasico and other matches to follow.
Only an MRI scan, which the Spanish international will undergo in Barcelona on Wednesday, will confirm the diagnosis and prognosis for certain.
AS continued: "If a tear is confirmed, the recovery period could range between four and five weeks."
For Flick, the setback piles on top of the injuries to Jules Kounde and Eric Garcia in the last match against Real Betis in La Liga.