Pompey grab points in second half ...Portsmouth closed the gap at the top of the table as they grabbed a victory at Brunton Park with three second half goals to inflict a fifth defeat of the season on the Cumbrians.
Striker Jamie Proctor had the ball in the back of the net with just two minutes on the clock, when he nodded a ball forward from Gillesphey past Forde, but the flag went up for offside just as the crowd started to celebrate.
Portsmouth responded with a quick break from deep and Baker spotted a gap as he took control. He struck the ball low and Gillespie had to dive long to palm it away.
The action moved to midfield as the sides worked hard to master the windy conditions and the Cumbrians were forced into an early change when Shaun Brisley went down with a cut to his head. Tom Miller came on at right back and Gary Liddle moved across to the centre of the back line.
Carlisle settled into their new shape and they created a good opening when Joyce and Proctor exchanged passes on the half way line. The mobile forward spotted Adams making a run and the nippy man drilled a shot across the keeper as he tried to find the bottom corner. Forde was equal to it as he went long to make a two-handed save.
United were awarded a free kick midway through the half when Proctor was dragged to the floor on the edge of the box, but the effort from Jones smashed into the wall as he tried to find the top corner.
There were huge appeals for handball when determination from Jones and Joyce left Tom Miller with room to exploit. He went for the first time shot but the referee turned away as the blue shirts asked the question when it appeared to hit a hand.
Carlisle had to make another substitution ahead of the break when Raynes came out of a challenge holding his calf. Alexander McQueen came on at left back and Gillesphey stepped across to take the centre half role.
Gary Roberts curled a 23-yard free kick just past the upright as Portsmouth tried to take advantage of the changes, but it was Carlisle who felt aggrieved when Evans clearly handled a high ball inside the area. The referee somehow missed it, as did his assistant, and nothing was given.
United momentarily lost concentration and a ball across the face of their area caused problems as it hit Liddle and then Miller. Eoin Doyle had time on his side, just three yards out, but he lost his bearings and smashed the easy chance over the bar.
A panic at the back allowed Bennett to cross at the start of the second half and some nervy defending left Roberts with a close range finish. United were relieved to see the offside flag go up.
There was also panic at the other end when Forde took a heavy touch as he came under pressure from Proctor. The keeper had to get it right as he slid in to recover the situation.
Wide man Nicky Adams took matters into his own hands when he went on a 40-yard run to turn defence into attack. He beat two but his cross was too close to the stopper.
Superb back to front football carved Portsmouth to pieces as Gillespie played the ball flat to Joyce from inside his six yard box. Four passes later Joyce was back on the ball and his cross was perfect for Proctor. The striker got there with his header but he was disappointed when he could only guide it past the target.
Both sides were going for it and Gillespie pulled off a a triple save as a swirling ball spun free inside the six yard box. Baker unleashed a volley, as did Roberts, but the Carlisle keeper set himself to make the much needed saves.
There was no time at all to draw breath and more slick passing put O’Sullivan on the overlap with plenty in support. He cut it back for Lambe and the winger brought an excellent save out of Forde as he fizzed a crunching shot at the target.
Half chances kept coming, with Gillespie alert as he punched a stinger from Michael Doyle wide, and Burgess had to cover in his own half when Proctor tried to get on the end of another Adams teaser.
It was excellent entertainment and Proctor and Adams linked again as he used Ibehre as a bounce board on the way forward. Burgess was the man to get the defensive touch again as Proctor tried to ghost in.
But it was the predator Gary Roberts who grabbed the lead for the visitors when he ran from deep to get past two men. He clipped the ball with the outside of his foot and Gillespie could do nothing as it hit the back of his net.
The points were wrapped up by the visitors when Amine Linganzi brushed Jones aside with brute strength and force. His next touch was a shot which literally flew into the back of the net.
And substitue Jack Whatmough grabbed a third when he was left in acres of space deep into time added on.
Portsmouth - Roberts (73), Linganzi (86), Whatmough (90)
Carlisle United - O'Sullivan (39), T Miller (62)
Carlisle United - Gillespie, Liddle, Raynes (McQueen 36), Brisley (T Miller 15), Gillesphey, Joyce, Jones, Lambe, O'Sullivan (Ibehre 60), Adams, Proctor. Subs - Crocombe, Bailey, Devitt, G Waring.
Portsmouth - Forde, Stevens, Clark, Burgess, Baker (Whatmough 71), M Doyle, Roberts (Naismith 80), E Doyle, Bennett (Chaplin 71), Linganzi, Evans. Subs - O'Brien, Rose, Lowe, Hunt.
Referee - Mr Richard Clark
Attendance - 7,197 (1,209 away fans)