Barcelona said Wednesday that Brazil midfielder Philippe Coutinho must undergo surgery after suffering a knee injury.
The Spanish club said in a statement that Coutinho had injured “the lateral meniscus” of his left knee and it will require “arthroscopic surgery”.
Coutinho, 28, was hurt in the final minutes of Tuesday's 1-1 draw with Eibar after he came on in the second half.
He became Barcelona's most expensive signing when it paid Liverpool 160 million euros ($192 million) in Jan. 2018.
But after a disappointing season-and-a-half Coutinho was loaned to Bayern Munich.
He helped the German club win the Champions League earlier this year and scored two goals in an 8-2 rout of Barcelona in the quarterfinals.
He returned to his parent club this season and has scored three goals.
Barcelona has already lost forward Ansu Fati and Gerard Pique to serious injuries this season. The team is struggling and has slipped to sixth in the Spanish league.