Freiburg captain Julian Schuster could struggle to play again before the Bundesliga's winter break after picking up a foot injury.
Schuster, who missed the weekend's home defeat by his former club Stuttgart, is likely to be sidelined for six weeks with the problem.
The 28-year-old is out of contract at the end of the season and his absence is the latest injury blow to hit Freiburg.
A club spokesperson told Deutsche Presseagentur: "Julian Schuster has sustained a foot injury, he is likely to be unavailable for the next few weeks of games."
Freiburg director Klemens Hartenbach added to kicker-Sportmagazin: "It's truly an unsatisfactory situation that our manager has been unable to field his ideal XI in any of our 18 matches this season."
The club currently sit 16th in the Bundesliga after picking up eight points from their opening 12 games and have five more league fixtures before the winter break, the last of which is against Hannover on 21st December.
Freiburg also face Slovan Liberec and Sevilla in the Europa League, with the German outfit trailing both those clubs in Group H.