Werder Bremen midfielder Tom Trybull could be out for the rest of the season with an ankle injury.
The 20-year-old will undergo an operation on his right foot in Munich on Wednesday but admits that he may not return to action this campaign.
"It's really just a routine procedure which hopefully will clear up my pain," he told the club's official website.
"Of course it's my goal to return to the pitch as quickly as possible. But I know that it will be tight."
Trybull had only just returned for Bremen from a long-term injury.