It has been a bad week for Rover's boss Ian Atkins. Fined Â£850 by the FA for verbally assaulting another manager, seeing his star striker Junior Agogo in court accused of attempted rape, and now taken to a cup replay by a non league side.
Without quite suggesting they would win, Carlisle came from behind a minute after Rovers had thought they had the tie won to deserve their replay.
Richard Walker scrambled in a free-kick off the post to put Rovers in front, but Brendan McGill then drove in the equaliser after home keeper Kevin Miller had flapped at a long ball from Chris Lumsdon.
It all set up a final 12 minutes of typical old style cup football with drama in both goalmouths. Carlisle then so nearly booked a clear place in round two before sub Keith Henderson's drive from the left of goal was turned on to the bar by Miller.
Second in the Conference and unbeaten away, Carlisle showed early on they were no underdogs. With Chris Billy running the midfield they were always looking to expose weaknesses in Rovers' defence.
No one picked up Simon Grand on one run as he sent a Lumsdon free-kick flying over the bar. On another run Miller had to grab his snapshot from above his head.
Rovers were grateful more than once for Christian Edwards' power of recovery, but the non-league side wasted the best opportunities that came their way.
They wanted just too much time in front of goal and Rovers were grateful for that.
The best chance for Carlisle came just before the break when Karl Hawley broke on the left. With the Brazillian Magno Vieira free in the middle, Hawley went for his shot and hit the side netting.