Hamburg have been rocked by the news that midfielder Petr Jiracek is set to be out of action for at least four weeks.
The Czech Republic international suffered a groin injury during training last week and the extent of the damage has now been revealed.
Hamburg admit the best outcome would be a return within a month, while some reports suggest Jiracek may even be sidelined until the middle of January.
"Petr Jiracek is injured. He will be out for action, at least for four weeks," Hamburg head coach Thorsten Fink told Deutsche Presseagentur.
"It's a new blow for him as much as for us. He has not had the best of starts to life at our club with his injuries and suspensions."
Jiracek, 26, has only been able to make five appearances for Hamburg since joining the club from Bundesliga rivals Wolfsburg in August, having been sent off in one game and had a thigh problem.