Bayern Munich striker Miroslav Klose could miss the rest of the season after suffering a possible broken ankle in the 3-0 win at Bochum.
The Germany international had to be substituted midway through the first half after he appeared to get his foot caught in a hole.
Klose will undergo tests in Munich to discover the extent of the injury, with boss Jurgen Klinsmann saying: "We hope that it is not so bad because we don't have much cover at the moment, but that is the way things are and we will have to cope with it.
"Given Klose's precarious situation, this win is good. For us, it is pleasing and comforting to go home with this result."
Klinsmann is already without Luca Toni due to injury while Landon Donovan's loan spell from the Los Angeles Galaxy ended last weekend.