Record signing Javi Martinez will miss Bayern Munich's Champions League game at PSV Eindhoven on Tuesday.
Martinez suffered a thigh muscle injury against Augsburg at the weekend and was replaced by Mats Hummels after 29 minutes of Bayern's 3-1 victory.
Bayern boss Carlo Ancelotti, speaking after the game, said: "He wasn't feeling good. He felt something in his muscle and I didn't want to take any chances."
Having only recently returned to full fitness after suffering an adductor injury, Martinez was rushed back to Munich for an immediate diagnosis.
Bayern confirmed on Sunday that the Spain international will miss the trip to Eindhoven with a left thigh muscle injury.
Meanwhile, Holger Badstuber continued his comeback from injury at the weekend, making a second substitute appearance in four days against Augsburg after breaking his ankle in February.
Defender Rafinha also returned to training on Sunday after recovering from a groin injury.