Jamie Devitt came off the bench to score a fine winner as Carlisle chalked up a fourth away league victory of the season with a 1-0 success at Colchester.
The former Hull trainee grabbed the only goal of the match when he latched onto James Brown's excellent pass to finish superbly across goalkeeper Sam Walker and into the bottom corner after 58 minutes.
Carlisle keeper Jack Bonham did well to save Kyel Reid's low shot at his near post early on and then denied Brandon Hanlan in similar fashion just minutes later in a first half that brought little goalmouth action.
Colchester almost broke the deadlock in the opening two minutes of the second half when Bonham made a superb double save to deny Sean Murray and then Hanlan from close range, after Ryan Jackson had done brilliantly to advance and deliver a cross.
But Carlisle went ahead just before the hour mark when half-time substitute Devitt popped up for his first goal of the season.
Bonham made another fine low save to thwart Drey Wright with 10 minutes remaining as Colchester pushed for an equaliser but Carlisle held out for victory.