Clint Hill's header proved enough for Carlisle to pick up a 1-0 win at Grimsby.
The former QPR defender struck midway through the second half to give Keith Curle's side all three points at Blundell Park.
Grimsby should have been ahead early on as Scott Vernon forced a good save from Jack Bonham, before Diallang Jaiyesimi somehow managed to hit the crossbar from just a couple of yards away.
Bonham was called into action again just before half-time as he produced a magnificent save to keep out Danny Collins' header, before James McKeown had to react quickly at the other end to prevent Richie Bennett from giving the visitors the lead.
Carlisle went close after the break when Reggie Lambe's cross form the right found Hallam Hope, and the striker's header forced McKeown to tip the ball over.
There was nothing the goalkeeper could do though when Hill met Gary Liddle's cross from the right, and flicked his header in at the near post to give the visitors the victory.