The Blues fell to defeat on the road following a brilliant second-half strike from Scott Sinclair.
Josh Vela latched onto a deep cross and hammered home to break the deadlock, on 16 minutes.
Bristol Rovers restored parity on 34 minutes, courtesy of striker Chris Martin, before Scott Sinclair found the top corner in superb fashion early in the second-half to seal all three points for the hosts.
The opening exchanges provided little in terms of chances for both sides with the first big opportunity falling to the Gas’ attacker Chris Martin on ten minutes, but he ultimately nodded wide.
Four minutes later, United came close to breaking the deadlock as Fin Back headed across goal to Luke Armstrong, but the latter was unable to steer his header on target.
The Blues gained the advantage on 16 minutes, a deep cross found Vela at the far post and the midfielder lashed home from close range to the delight of our travelling support.
The hosts started to grow into the contest soon after and Harvey Vale forced Lewis into a strong low save at his near post, before Back found Armstrong at the opposite end, who fired wide.
On 32 minutes, we came agonisingly close to extending our lead as Taylor Charters rattled the post.
Two minutes later, Bristol Rovers equalised as Chris Martin stabbed home from close range against the run of play and they almost took the lead soon after, but the intervention of Back proved vital for United.
Carlisle won a corner as we entered stoppage time at the end of the first-half, but nothing came from it in the end.
Half-time: Bristol Rovers 1-1 Carlisle United
An early second-half corner for United provided chances for both Armstrong and Jon Mellis from point blank range, but neither were able to put us ahead once again.
On 51 minutes, Scott Sinclair cut inside from the left and wrapped an effort into the far corner beyond the reach of Harry Lewis to give the hosts the advantage.
15 minutes later, the Blues looked to catch the Gas on the break as Vela picked out Diamond sprinting forward, but Kamil Conteh managed to scramble back and clear the danger.
Soon after his introduction, Jack Ellis slid a ball down the line to Diamond, who won United a corner which was met by Lavelle, before a chance also fell to the feet of Harrison Neal on the edge of the box, but neither tested Jed Ward in the Bristol Rovers goal.
The hosts came close to furthering their lead on 78 minutes, but an initial effort was tipped onto the post by Lewis, before Vaughan fired at goal but was deemed offside.
Ellis came to the rescue for the Blues on 82 minutes, clearing the danger following a Jack Hunt cross from the right.
On 88 minutes, Martin had the chance to wrap up the three points for his side, but he hammered wide from inside the Carlisle area.
Lavelle had a wonderful opportunity to bring us back on level terms following a free-kick, but our skipper shot wide, on 95 minutes.
Full-time: Bristol Rovers 2-1 Carlisle United
Goals
Bristol Rovers: (Martin 34’), (Sinclair 51’)
Carlisle United: (Vela 16’)
Bookings
Bristol Rovers: (Hunt 22’), (Thomas 50’), (Marquis 90+4)
Carlisle United: (Neal 56’), (Armstrong 90+3)
Teams
Bristol Rovers: Ward, Gordon, Wilson, Sinclair (Crama 87’), Thomas (Vaughan 77’), Martin, Vale (Marquis 89), Brown (Grant 82’), Conteh, Baggott, Hunt
Unused subs: Cox, Connolly, Hoole
Carlisle United: Lewis, Back (Ellis 67’), Lavelle, Mellish, Armer, Neal, Vela, Gibson (Butterworth 67’), Charters (Maguire 87’), Diamond (McCalmont 87’), Armstrong
Unused subs: Breeze, Huntington, Grehan
Match Officials
Referee: Thomas Parsons
Assistant Referee 1: Alan Cresswell
Assistant Referee 2: Andrew Aylott
Fourth Official: Kevin Howick
Attendance: 8,679 (468 away)