Bayern Munich star Lena Oberdorf has been ruled out for several months after tearing her anterior cruciate ligament (ACL) in her side's 5-1 victory over Koln on Sunday.
The injury comes just one month after Oberdorf returned from a cruciate ligament injury she sustained while playing for Germany in June last year.
Bayern confirmed on Monday that the midfielder suffered a cruciate ligament tear in her right knee, the same one which forced her out for 16 months last year.
"This news hits us all very hard and we feel for Lena. She worked tirelessly and with great desire to come back after her first injury," Bayern Munich director of women's football Bianca Rech said.
"To now face a second such setback is incredibly hard. We are fully by Lena's side, will support her as best we can in her recovery and be there for her in every way."
Oberdorf will undergo surgery on Tuesday. She was expected to return to the national team in Friday's Nations League clash with France after being called up to Christian Wuck's squad.
After returning to the pitch in September, Oberdorf was regaining form with a brace in a 3-0 victory over RB Leipzig.
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Oberdorf is one of a handful of players who have already faced ACL injuries so far this season. National teammate, Giovanna Hoffman, and Bayern teammate, Sarah Zadrazil, both sustained the injury erlier this season.
Arsenal goalkeeper Manuela Zinsberger and Liverpool's Marie Hobinger both suffered ACL injuries a week apart.
France's Liana Joseph also faces an extended period on the sidelines after suffering the same injury against Arsenal in OL Lyonnes' opening game of the Women's Champions League.