Danny Grainger has sustained a knee injury which could keep him out of action for up to nine months.
The Hearts defender needs surgery to repair damage to his anterior cruciate ligament after picking up the injury against Motherwell on Saturday.
The 26-year-old told the club's website: "To say I'm gutted is an understatement. I'm going to miss the rest of the season.
"I need an operation which means I'll be out for six to nine months.
"I have had lots of kind messages from footballers and fans, which has been overwhelming."
Grainger will undergo the operation in two weeks' time.
