Frank Ribery and Medhi Benatia have been ruled out until after the winter break, Bayern Munich confirmed on Friday.
The news on Ribery will be particularly frustrating for Bayern boss Pep Guardiola, who has finally been able to use the Frenchman in recent weeks after a nine-month lay-off due to an ankle injury.
Ribery came on as a substitute and scored in last weekend's surprise 3-1 defeat at Borussia Monchengladbach and subsequently started Wednesday's Champions League victory at Dinamo Zagreb.
He was replaced at half-time, however, and tests have shown an unspecified muscle injury that will see him sit out Bayern's three remaining games prior to Christmas.
Benatia also started in Zagreb before being replaced at the break.
The Morocco international has struggled to convince since joining Bayern from Roma in August 2014 for an initial fee of €26 million.
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