Injured Carlisle United duo Morgan Feeney and Fin Back are set to miss the rest of the season.

The hamstring injuries both players suffered at Leyton Orient have ended their campaign prematurely.

Luckless Back could be facing surgery again, with a muscle tear that will rule him out for 12 to 16 weeks.

And manager Paul Simpson said captain Feeney’s injury, although not as severe as Back’s, will sideline him for eight to ten weeks.

Simpson said centre-half Feeney would have an outside chance of playing in the play-off final should United be involved in it.

But otherwise the Blues must plan without the pair.

It is a double blow ahead of Carlisle’s Good Friday clash with Tranmere Rovers as they look to get back to winning ways.

Nottingham Forest loanee Back had only just returned from an injury to his other hamstring - one that had kept him out since November - when he pulled up at Orient on his first game back last Saturday.

“Fin was described as a 3C hamstring tear, so 12-16 weeks he’ll be out, and will possibly need surgery again on his other hamstring,” Simpson said today.

“Morgan isn’t as bad – it’s a 2C but still probably eight to ten weeks. So the chances are they won’t be available again for this season for us.”

Simpson added that Back has returned to his parent club before the next course of action is determined.

Feeney does not need surgery, Simpson added, and is set to undergo a course of PRP [platelet-rich plasma] injections to aid his recovery.

Simpson insisted there had been no way of anticipating either injury.

"If you think an injury could have been avoided, that’s even more frustrating, but there was absolutely no sign of this coming into the game," he said. "They were both really innocuous situations.

"Morgan stretched his leg out to block a clearance and felt his hamstring pop, Fin got his studs caught in the ground and stretched his leg to try and intercept a ball and his went.

"Morgs said he had absolutely no sign of it before the game or during the game before it happened.

"With Fin we followed Forest’s plan exactly to the letter, and just something unusual on his other leg has caused that.

"The best-case scenario is we may get Morgan back if we were to make it to the play-off final. But with Fin he’s finished with us for this season."

United’s boss admitted it was a blow to lose both players but stressed that Carlisle had enough in their squad to defy the injury situation.

“They [Back and Feeney] are not in a good state but we’ve certainly got enough to be fit and put a good enough side out against Tranmere to cause them problems,” he added.

“The group we have available now have to step up to plate and do job for us."

In the respective positions of centre-back and wing-back, Simpson added: "I'm confident if we play the same system Corey Whelan or Ben Barclay can step in, and confident Joel Senior and Jack Ellis could play.

"If we wanted to be a bit more positive Jordan Gibson could do that [job on the right] like has done.

"This is where the squad comes into play. We've been really unfortunate with the injuries we've got, but we have other options and it's up to them to step up."

Owen Moxon, who suffered a knock against Orient, had trained all week and was fit to face Tranmere, Simpson added.