Zoltan Gera will be sidelined for the remainder of the season after sustaining another serious knee injury.
The 33-year old Hungarian midfielder went down in West Bromwich Albion's FA Cup draw with QPR on the weekend and will undergo surgery on his ruptured anterior cruciate ligament.
"I'm devastated for Zoltan," Clarke told the club's official website. "He's a terrific guy and professional and I want to thank him for his contribution this season. It has been invaluable.
"He'll now get our full support during the rehab process. Zoltan has already proven he can come back from this injury once and produce at the highest level and I have no doubts he will do so again."
Former Fulham man Gera had only returned to action this season after missing most of last campaign with a similar injury.