Ivan Perisic is a doubt for Bayern Munich's Champions League round of 16 meeting with Chelsea later this month after the Croatian fractured his ankle in training.
The 31-year-old joined Bayern on loan from Inter Milan this summer and has scored four goals in 15 Bundesliga appearances.
Speaking to his press conference this week, Bayern interim manager Hansi Flick said: "He has a fracture at the outside of his ankle.
"It will take at least four weeks until it is healed and only then he will be able to start with building up training again."
The Bavarian giants suffered a poor start to the Bundesliga season, with former coach Nico Kovac leaving the club in November as a result.