The Germany striker could be out for some time as he is set to go under the knife on a knock he picked up just 42 minutes into Saturday's Liga Total! Cup clash with Werder Bremen
The 27-year-old was stretchered off only minutes shy of the halftime whistle at the Imtech Arena in Hamburg, where it was later discovered that he would require an operation to rectify the problem.
Speaking on Sunday, Bayern sporting director Matthias Sammer admitted: "He is not good. He needs surgery. Then we'll see how long he's out for."
The match finished 2-2, with penalties deciding the match in favor of Bremen, who ultimately prevailed 4-2 from the spot after normal time.
The Germany striker follows the likes of Rafinha (torn knee ligament), Diego Contento (hairline foot fracture) and David Alaba (stress foot fracture) on the club's treatment table with long-term injuries.
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