Town striker Danny Schofield had gone close when he drifted past David Raven in the box and placed a shot just wide of Keiren Westwood, only for Danny Livesey to save the day and clear off the line. Irishmen Michael Collins was a constant thorn in Carlisle's side and he almost opened the scoring when he squeezed a shot just wide of Westwood from a tight angle.
Zigor Aranalde nearly grabbed an equaliser from a wind assisted 30-yard free-kick, but his effort flicked off a defender and flew agonisingly over the bar. Carlisle's Danny Graham then should have done better with a simple header, before the ever dangerous Garner found the net in first-half injury time.
Jeff Smith hit a deep cross to the far post and keeper Matt Glennon jumped to catch under pressure from Livesey. But the former Carlisle glovesman dropped the ball, and with the Town defence expecting a free-kick, Garner nipped in to thump the ball home from three yards out, for his fourth goal since joining on loan from Blackburn Rovers.
A resurgent Carlisle then dominated the second half, with Aranalde again hitting a venomous free-kick which Glennon smothered. Schofield had another shot cleared off the line late on in a rare Town attack, before Garner was harshly sent off in injury time. Running clean through with just Glennon to beat, the teenager appeared to be fouled, but referee Scott Mathieson produced a second yellow card for diving and sent him off.