Regan Linney grabbed his 20th goal of the season for Carlisle as they scraped a 1-0 win at Halifax to remain clear in third place.
The Cumbrians thumped Boston 6-2 at the weekend and followed that with a nip-and-tuck victory at The Shay, converting with their only concrete chance.
Linney latched on to a deft pass from full-back Jack Ellis in the 68th minute and found a finish as he slotted past Sam Johnson.
Halifax saw Gabe Breeze save from Josh Hmami as they attempted to salvage a point and are clinging on to the final play-off spot, with Southend and Hartlepool chasing.
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