Hertha Berlin skipper Arne Friedrich could miss the rest of the season with a knee injury.
The German defender sustained the injury in the 3-1 defeat to Borussia Dortmund at the weekend.
Due to have an operation on Wednesday, Friedrich is set for a four-to-six week absence at a crucial stage in the campaign as Hertha press for the Bundesliga title.
Saddened by the news, the 29-year-old remains hopeful he will play again before the end of the season.
"This is extremely bitter because I wanted to help the team in this crucial phase," he told the club's official website.
"I hope to play again during the season and that is my goal."