Crystal Palace fear Cheick Doucoure could be out for the rest of the Premier League season.
The defensive midfielder is a key player for Roy Hodgson, and was wanted by top clubs in the summer transfer window.
The 23-year-old Mali international has a serious Achilles tendon injury that will require extensive rehabilitation.
Post-game, Hodgson said: He's got a bad injury. I'll let the doctor deal with that first.
It's not going to be an injury that keeps him out for a short period of time."
Eberechi Eze was also substituted with yet another injury as he struggles to maintain his fitness this season.