Striker Mark Cullen will be out for five to six weeks with a groin injury, Carlisle United boss Steven Pressley has revealed.
The Blues manager said the Blackpool loan man suffered a grade two tear during Saturday's victory against Swindon.
It means January signing Cullen will miss much of United's run-in.
The news came on an already bad night for the Cumbrians, who suffered a poor 3-1 home defeat to Notts County to fall back out of the play-off places.
Cullen had to be substituted in the first half of his sixth Blues appearance at the weeknd, after which the injury was scanned.
Pressley said: "It's a grade two tear, so it will be five to six weeks.
"It's a long-term one so it's really disappointing."
Pressley said Cullen would remain with United for treatment rather than return to his parent club.
"He'll remain part of the group and hopefully we'll get him back before the season ends," the manager added.
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