Ross County midfielder Ross Callachan is facing an extended period on the sidelines after revealing that he ruptured his anterior cruciate ligament in Sunday’s defeat by Celtic.

The 29-year-old only came on as a substitute in the 84th minute of the match against the cinch Premiership leaders but he was forced off early after injuring himself in the closing stages.

Callachan announced on Instagram on Thursday afternoon that he has suffered campaign-ending damage to his knee. He is not expected to be fit again until well into next season.

“Gutted to be posting this but in Sunday’s game I ruptured my acl,” he said. “This will be a lengthy recovery/rehab process but I’ll do everything in my power to be back playing and enjoying football again.”

The news comes as a big blow to County, who are just two points ahead of bottom-placed Dundee United in the battle to stay in the Premiership.