In-form City recorded a fifth straight League One victory with a battling performance at Carlisle United.
Ben House fired the Imps into an early lead at Brunton Park, with Joe Taylor doubling City's advantage early in the second half.
Sam Lavelle pulled one back as the relegation-threatened hosts fought hard, but Ted Bishop made the result safe with a stunning free-kick in time added on.
Head coach Michael Skubala made one change in his team selection, with Ethan Erhahon returning from his one-match suspension - he came straight back into the line-up to replace the injured Danny Mandroiu, with Ted Bishop moving into a more attacking role alongside Jack Moylan.
There was one further change before kick-off, with Lukas Jensen pulling up during the warm-ups with an injury. This meant Jordan Wright stepped up to start in goal.
Wright was the first keeper called into action, as he got down well to his right to turn a Dan Butterworth shot behind.
Four minutes later, Cumbrians' keeper Harry Lewis was picking the ball out of the back of his net after City's first strong attach. Lasse Sorensen's cross from the right found Joe Taylor, who unselfishly pulled the ball back for House to half-volley home.
City were not lacking in confidence before the goal, but then took control and enjoyed lots of possession in the Carlisle half.
It took a vital interception from Jack Ellis to stop Reeco Hackett getting on the end of a great low Bishop cross after 16 minutes, and a couple of minutes later Paudie O'Connor saw a half-volley blocked.
Ellis also pulled off a brilliant block to deny Taylor after he cut inside and looked to get a shot away. Taylor also tested Lewis with a looping after 26 minutes, from Hackett's cross, but the home keeper had his angles covered.
Wright was required again after 32 minutes, punching away a corner the home side had won when Jon Mellish's shot was deflected behind. The cleared ball fell to Jack Robinson, but he lifted his effort over the bar.
City continued to create the best chances of the first-half, with O'Connor again getting on the end of a Bishop corner to head the ball back into the area - with Harrison Neal getting a vital clearance before Reeco Hackett could turn the ball home.
Lavelle blocked a Bishop shot, and the last action of the first half was the home keeper Lewis holding Taylor's low shot from outside the area.
The home side were clearly fired up as they started the second half fighting for their survival in League One.
Wright pulled off a brilliant save within seconds of the restart after Mellish flicked a header towards goal - tipping the ball over for a corner. Butterworth clipped the outside of a post from the resulting corner, and Wright held Jack Armer's header.
It was a frantic opening five minutes of the second period, but the home side were inevitably leaving themselves open on the counter-attack and City doubled their lead after 53 minutes through a move which started with them clearing a corner.
House led the move breaking past the halfway line, before feeding Taylor who calmly slotted into the far bottom corner.
The home side were not ready to give up, and Wright pulled off another stunning save to tip Butterworth's powerful effort over quickly after the restart.
The game became scrappy but neither side were creating too many clear chances, despite a run of corners for the home side just after the hour mark. Some determined blocks from the Imps saw out the danger.
Hpme manager Paul Simpson made a number of changes as he sought a way back into the game, while Michael Skubala also sent on Jovon Makama to replace Taylor.
Makama almost got his second goal in as many games after House won the ball off Jack Robinson and played in a low cross, but it was just too far ahead of City's young forward.
The home side did pull one back through captain Sam Lavelle with 10 minutes to go, as he hooked home a shot which left Wright with no chance.
O'Connor went close to getting on the scoresheet when he got ahead of Neal to turn Sorenen's free-kick towards goal, but Lewis did brilliantly to get a fingertip to the ball.
There were eight minutes of time added on, but City by now had control of the game.
And, when Bishop was fouled by home sub Josh Emmanuel three minutes into time added on, he dusted himself off to lift the resulting free-kick into the top right corner.
Imps: Jordan Wright, Alex Mitchell, Paudie O’Connor (c), Sean Roughan, Ethan Erhahon, Ted Bishop, Jack Moylan, Lasse Sorensen (TJ Eyoma, 88), Reeco Hacket (Adam Jackson, 83), Joe Taylor (Jovon Makama, 70), Ben House (Freddie Draper, 83). Subs not used: Lukas Jensen, Jack Burroughs, Dylan Duffy.
Carlisle: Harry Lewis, Jack Armer (Jack Diamond, 67), Sam Lavelle, Jordan Gibson (Sean Maguire, 67), San Butterworth (Georgie Kelly, 59), Jack Ellis (Josh Emmanuel, 58), Jack Robinson, Jon Mellish, Ben Barclay, Harrison Neal, Luke Armstrong. Subs not used: Gabe Breeze, Alfie McCalmont, Sean Grehan.
Attendance: 7,103 (724 away)