Carlisle United's Callum Guy is facing up to ten months out after suffering an ACL injury.
The midfielder suffered the injury at Leyton Orient last weekend - and assessments this week have confirmed the extent of the damage.
Manager Paul Simpson confirmed the news at his press conference this afternoon.
He said that a scan on Monday had confirmed the news the Blues feared and that Guy would be out for about nine to ten months.
"He has damaged his ACL [anterior cruciate ligament] in his knee," said Simpson.
"He has been to see the surgeon today - the surgeon wants him [first] to have three weeks to try and get a full range of movement back into the knee.
"The plan at the moment is to operate about the first week in December.
"Unfortunately with this type of injury we're looking at nine or ten months out on the sidelines, and we've just got to make sure we look after Callum now."
Simpson described the news as a "massive blow" for Guy, the rest of the players and the whole club.
But he said the midfielder was a "strong character" who would face his long spell on the sidelines with the right mindset.
"He'll have some low moments, some dark times and we've got to get him through it as best we can," added the United boss.
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