Carlisle United 0 Tranmere Rovers 2: This was, in the end, League Two distilled into 14 minutes, where all results are possible, none of them a surprise.

Between the 76th minute and the 90th, Carlisle could have won 1-0 but also might have lost by three. At the final whistle, they dropped from fourth to 11th, but remained three points short of second. They lost at home in the league for the first time, yet John Sheridan felt it was as well as they have played.

Go figure. In this land of fine margins, of unpredictability, of Newport 0 Yeovil 6, of making your own luck, everything is still at the mercy of being able to capitalise on it, otherwise it can go dramatically the other way.

The cold-eyed reading says United should have been home and hosed before this game's crucial final stages. It's true that they missed decent openings and failed to turn pressure into potency.

Shy boys don't get sweets, and a side that’s blunt in the final third can't expect points. Yet even then, Sheridan's side were a knife-edge away from a narrow victory that would have had us purring about a top-three position.

Their move of the match, which conceived their penalty, was splendid: Gary Liddle popping up in nosebleed space for a centre-half playing at right-back, and playing a smooth one-two with Adam Campbell to go through on goal.

Maybe he should have scored and removed all doubt. He didn't, yet he was convincingly felled by Tranmere keeper Scott Davies - who then changed the course of the entire game by saving Jamie Devitt's penalty.

Minutes later, United up against a newly-emboldened visiting side, Tom Parkes had accidentally prodded the ball into his own net and another Carlisle mistake (from Jack Sowerby) had opened the door for Paul Mullin's excellent second. Before it was done, Tranmere had also hit the crossbar and wasted two other great chances, en route to their best away win since April. Their only away win since April.

Their supporters, probably as vocal as Brunton Park's away section will house all season, were jubilant. Good luck to them. Many Carlisle fans will remember how it feels to bounce back from non-league with an extra puff of wind in one's sails. Away days such as theirs on Saturday feel very good indeed.

As for United's players, they must work at those margins, and be particularly ruthless on their final-third play, but not, Sheridan said, "cry themselves to sleep". He added: "It's just the way it works. We move on. I don’t want to dwell on it or think about it. I told the players I thought we played really well."

In several respects Sheridan was right: United, after an iffy start, grew into the contest and looked the more likely side. In midfield Kelvin Etuhu stood out and they kept James Norwood, the EFL's leading scorer, at several arms' lengths.

There were flaws, though, in certain departments. Service to their frontmen was at times lacking while those frontmen themselves did not have their best of days. Tranmere's centre-half, Steve McNulty, has been defying his less-than-sleek appearance for years but still the Blues played too often and too obviously into his steady hands.

Without George Glendon in midfield (Hallam Hope returned as another attacking body), Carlisle took longer to gain control than they would have wished. Tranmere started well, Connor Jennings almost feeding Norwood early on, the striker then shooting close from 25 yards and Ollie Banks doing similar from further out.

A while later, Cole Stockton showed anticipation to pick up Devitt's miscontrol and test Adam Collin's reflexes from 30 yards. This did not herald a point-proving display from Stockton against the club for whom he failed to impress last season, but United still had to deal with his hold-up play more than they examined McNulty and Manny Monthe from the outset.

Eventually this changed, chances being punched out of some persistent, if not always fluent, work. Richie Bennett's head looped a Devitt cross onto the top of the crossbar from a good position, and Hope crossed marginally out of Ashley Nadesan's sliding reach as Carlisle finally found some pressure.

Devitt, in the centre, almost threaded Nadesan and Hope through further times and looked like Carlisle's most likely lockpicker. At other stages, their diagonal aiming for Hope on the left was overdone, yet they were still on top as the half went on, Bennett getting a header all wrong when an expected offside flag stayed down, and Devitt whipping an attempt onto the roof of the net after a short corner.

The fact Hope and Jerry Yates swapped wings a couple of times either side of the break suggested, though, that Carlisle had had some difficulty in breaking past Micky Mellon's full-backs. Neither was at his most penetrating yet, with Etuhu showing sharpness to win back the ball and impose himself more on Tranmere's midfielders, a game was there to be won.

That final step proved beyond them. Early in the second half, Sheridan introduced Sowerby for Yates and sent Devitt to the right. The Irishman went close from 25 yards, threw himself at a Liddle cross then saw Nadesan fail to take a promising ball cleanly in his stride as the Blues had a further flurry.

Macaulay Gillesphey then failed by inches to serve Bennett from the left, but finally came the best opportunity of all. Devitt's penalty, though, was not his most deadly, Davies' correct guess rewarded as he dived to his right to meet the kick at a friendly height. The "Super White Army" in the away section roared, and four minutes later did so again, as Jake Caprice found space on the right, and Parkes found himself a split-second behind events, facing his own goal and diverting the dipping cross past Collin.

Margins. But crucial ones. Five minutes later, Sowerby stumbled on the ball and was raided by Mullin. The rest was top quality, the substitute cruising infield and curling his shot past Collin.

And that was that, a rapid burst of three more Tranmere chances aside - Jonny Smith saved, Norwood the bar, Mullin over it - and, for Carlisle, an injury-time cameo for Liam McCarron, and hence a league debut for the 17-year-old.

That was, at least, a positive note on which the Blues could end (Campbell's invention, which surely makes a case for a start soon, was another). They were the only notes Sheridan was willing to play afterwards, in fact.

"I thought we were excellent, honestly," he added. "I thought we played really, really well. I'll take it on the chin." Just not too many more times, you hope, in a division that specialises in the strange and the precarious.

United: Collin, Liddle, Gillesphey, Parkes, Gerrard, Etuhu, Devitt, Hope, Yates (Sowerby 54) Nadesan (Campbell 73), Bennett (McCarron 90). Not used: O'Reilly, Miller, Glendon, Slater.

Booked: Devitt, Parkes

Tranmere Rovers: Davies, Caprice, Bakayogo, McNulty, Monthe, McCullough, Mottley-Henry (Smith 73), Banks, Jennings, Stockton (Mullin 69), Norwood. Not used: George, Buxton, Ellis, Gilmour, Cole.

Goals: Parkes 80(og), Mullin 85

Booked: Banks, Davies

Ref: Matt Donohue

Crowd: 5,187 (796 Tranmere fans)