German magazine Kicker claims Franck Ribery's thigh injury is worse than first thought and the Bayern Munich star is set to miss the next eight weeks.
The 32-year-old former France winger has endured a miserable 2015.
He tore his thigh muscle in Bayern's Champions League game at Dinamo Zagreb last week, on just his second appearance after nearly nine months out with an ankle injury.
The Bundesliga breaks for four weeks on Sunday, and Ribery is expected to be on the sidelines for the next two months, meaning he will miss the restart on January 22 when leaders Bayern are at Hamburg.
Kicker reports Ribery's injury has caused tension between Bayern coach Pep Guardiola, who is set to announce his future before Christmas, and team doctor Volker Braun, who believes the French winger was brought back too early due to a long casualty list.
Bayern have a five-point lead in the table and face Hanover away on Saturday in their final game of 2015 with Arjen Robben, Douglas Costa, Medhi Benatia and David Alaba all out.