Serbia midfielder Gojko Kacar has joined Hamburg's nine-strong list of walking wounded after limping out of the defeat to Bundesliga leaders Dortmund with damaged ligaments in his right ankle.
The 23-year-old came off after just 30 minutes of Hamburg's 2-0 defeat at Dortmund on Friday which allowed the home side to open a seven-point lead at the top of the table before Saturday's matches.
Kacar is thought to have torn ankle ligaments and joins forwards Ruud van Nistelrooy and Eljero Elia, midfielder Marcell Jansen, defenders Dennis Aogo and Dennis Diekmeier and goalkeeper Frank Rost on the injury list.
In total, Hamburg have nine players out injured and €5.5m Kacar is expected to be out for several weeks.
"It's a bitter blow," said Hamburg's director of sport Bastian Reinhardt. "For the first time we managed to keep the same starting line-up and that lasted just half an hour."
Hamburg were seventh in the league table before Saturday's round of matches.