It was a third home game within the space of eight days for the Blues with Crawley Town the visitors.
There were two changes from the team that faced Cambridge on Saturday, with Jack Armer and Lewis Alessandra in for Nick Anderton and Dean Furman.
United attacked the Waterworks End in the first half and there was a superb team move from the off when Zanzala spun his man before breaking away, halfway inside Crawley territory. He fed it to Mellish, who had three attackers to choose from, but the flag was up for offside as they looked to finish things off.
A cross from Wright bounced awkwardly inside the United six-yard box at the other end and it spun deceptively over Tanner when it sprang off the surface. Allarakhia had his back to goal and the home defence regrouped to see it off.
Carlisle looked lively and Patrick took a run across the face of the area with the ball at his feet. He checked back, before coming the other way, and his eventual effort was blocked.
Riley employed his long throw on 10 minutes and a poor clearance sat up for Armer to strike, 18-yards out. He applied power, but it ricocheted off McDonald and angled harmlessly wide.
Another throw was headed back to Riley by McNerny, and his neat cut back was met by McDonald on the volley. He tried to guide it but it was always high, from the moment it left his boot.
The Cumbrians crafted a good opening when Riley and Tanner exchanged passes out wide. Alessandra moved off his man as he showed for it, and he intelligently slid the pass to the opposite edge of the area, where Armer had arrived late. He set himself to shoot but he dragged it into the ground.
Crawley were carved open again when Mellish came out of the pack with the ball at his feet. Patrick wanted it, and he fed it on for Armer to hit. His shot turned into a cross and the Red Devils were pleased to get it away.
It was a short-lived reprieve though as Riley stepped inside from the left wing, with options ahead. He chose to shoot from distance, and Morris couldn't believe his bad luck as it spooned off a lump of mud, over his head and into the net.
Keeper Glenn Morris was needed when Alessandra worked space 25-yards out. His drilled attempt was going in until two hands parried it. Blue shirts camped forward and Guy was next to have a pop when he unleashed one from distance. Morris saw it late and he could only beat it away.
A fantastic passage of play followed, with Alessandra, Patrick, Mellish and Riley keeping things neat, and Tanner gave a shout as he overlapped. His cross found Zanzala on the dive but his 12-yard header crept agonisingly wide, with the stopper well beaten.
Striker Omari Patrick registered a real goal of the season contender on 33 minutes when he took a long ball forward on his outstep. He turned away from his marker, took a moment to assess things, and then stepped forward before putting his laces through it. Morris was caught completely off guard as the effort from distance whistled into his top corner.
Home tails were up and Alessandra wound his way through two challenges before he reached a shooting position. It was on target, but a red shirt got in the way.
Crawley offered little as an attacking force in the first period but an inswinging free kick from Powell caused teeth to be sucked as it evaded everybody. Farman was comfortable as he watched it go behind.
Tanner then had to nod a deep cross behind to safety, as Nichols sent one in, and the corner was subsequenty cleared.
A slick Carlisle move welcomed the start of the first half with Patrick and Armer keeping it close before bringing Alessandra into the mix. He slipped it through for Mellish to chase, and his first-time delivery was met on the run by Zanzala. A clipped header was gratefully gathered by Morris.
The Red Devils responded with a ball forward that Allarakhia trapped. He dropped a shoulder and crossed, but Farman was out to punch. A foul in the scramble that followed gave Crawley a chance from a 24-yard free kick, but Powell whipped it over the angle of post and bar.
Powell sent one even higher when he was presented with another free kick opportunity, this time from 30-yards.
Carlisle were incensed when an away attack was allowed to develop despite the referee having seen Callum Guy fall to the floor covering his eye. A dangerous cross was cleared and the match official finally stopped play.
United were close to adding a third just past the hour when Guy ripped a great free kick at the near post. It wound its way through after Morris had palmed it, and Alessandra was there to volley it at the target. The keeper punched, and Zanzala was caught offside.
Talking about close, a Riley cross brought a bullet of a downward header from Zanzala from just eight yards out. Morris spread himself to block on the line, and the keeper was even better as he stuck out a leg to prevent the home forward from prodding the loose pieces over the line.
Morris was tested again as the hosts pressed on, with Riley fed by Patrick after Zanzala had shown fantastic strength to hold off McNerny. A dive from the away glovesman saw him get both hands to the shot.
Midfielder Callum Guy dipped a 28-yard free kick onto the roof of the net as the game entered the final quarter, and United knocked on the door again when a ball over the top was chased by Zanzala. He turned away, and gave it to Mellish, but the delivery that followed was charged down.
The Blues saw the game out well as they closed the gaps, and substitute Gime Toure rounded things off as he went on a run before seeing his effort hit a leg and drift into the keeper's hands.
Carlisle United - Riley (17), Patrick (33)
Carlisle United - Guy (77)
Crawley Town - McNerny (66), Craig (81)
Carlisle United - Farman, Tanner, Hayden (c), McDonald, Armer, Riley (Furman 90), Guy, Mellish, Patrick (Toure 86), Alessandra (Walker 89), Zanzala (Scott 89). Subs - Norman (gk), Anderton, Charters.
Crawley Town - Morris, Francomb (c), McNerny, Powell (Matthews 74), Nadesan (Tilley 86), Allarakhia (Davies 80), Nichols, Craig, Tsaroulla, Hessenthaler, Wright. Subs - Nelson (gk), Sesay, Maguire-Drew.
Referee - Robert Lewis
Assistant Referee 1 - David Avent
Assistant Referee 2 - Daniel Woodward
Fourth Official - Gary Hilton
Attendance - BCD