Lincoln were left to rule a first half penalty as Carlisle dumped them out of the FA Cup with two quick fire goals after the interval.
Imps boss Keith Alexander blasted his forwards saying, "We should have won. The penalty could have been better taken." He moaned, "Our strikers didn't work hard enough to take advantage of the chances we created".
Ben Sedgemore was the culprit for the penalty miss, opting for precision rather than power and for the second Saturday running Carlise keeper Matt Glennon saved from the spot.
United defender Darren Kelly saw red for his part in the incident. Peter Gayne hammered in an angled shot and Preston referee Graham Salisbury ruled hand ball.
His decision meant that Carlisle were down to ten men for the third Saturday on the spot but the Cumbrians didn't crumble.
Richie Foran opened the scoring in the 56th minute when he latched onto Ryan Baldacchino's incisive through ball to stroke home first time across Andy Marriot from the edge of the six-yard box.
Craig Farrell plundered the second after substitute Brendon McGill threaded a pass to the on-loan Leeds striker. Farrell drew the keeper before hammering in a shot from just inside the box.
Lincoln threw everything they had at Matt Glennon but the keeper was in magnificent form. Ben Futcher beat him in the 59th minute but his header from a Scott Willis cross thumped back off the cross bar and from the rebound Glennon made a superb double save to keep out Simon Yeo's diving header and turn Dean Cropper's shot onto the post.
Lincoln finally got a consolation goal in the 87th minute when Futcher was quickest to react to Stewart Bimson's corner that he netted from close range.
Carlise boss Roddy Collins said "We did great tactically, they never exposed us with their extra man. It was a great team performance. It was entertaining and very exciting with a cliff hanging finish"