Carlisle United boss on Portsmouth and Colby Bishop

The Blues head to the home of the League One leaders tomorrow.

And they will bid to become the first side to topple John Mousinho’s side in the league this season.

In order to do so, they will have to keep quiet eight-goal Colby Bishop, who is the division’s second highest scorer.

The former Leamington and Accrington Stanley man has spearheaded Pompey’s rise to the top of the table.

Blues boss Simpson said of Bishop: “He’s just got that hunger that you see in players who come through non-league.

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“He’s somebody who’s had to go out and do a proper day job [Bishop is a former primary school teacher].

“Looking at the games I’ve watched with him in it, he chases everything down so there’s no let-up for centre-backs – they’re going to have to be at it for the whole game.

“You know the way they play they’ll put crosses in the box – and he’s in the box.

“It’s a challenge, but it’s a brilliant one. If you’re going to achieve success by getting promoted, you have to be prepared to raise your level and compete against a better standard, and that’s what Portsmouth are showing at the moment.”

While United suffered a frustrating home defeat to Leyton Orient last time out, their previous league game saw the Blues beat one of the division’s other big hitters in their own back yard.

The 3-1 victory at Bolton Wanderers should give Carlisle confidence that they can handle themselves against the league’s high fliers.

“Portsmouth are different [to Bolton] in how they go about it,” said Simpson.

Portsmouth boss John Mousinho (Image: PA)

“They have a front four who are a real handful, in the two wide players, whichever of the number tens play and the striker Bishop.

“They’re a real threat. But it’s a game that we have to go and put our game onto them and try and cause them problems.

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“We’ve looked at quite a few of their games and identified areas where we think we can exploit.

“Nobody else has been able to do it this season but I do think that the longer these unbeaten records go on for, they’re going to end at some point.

“We’ve just got to approach it that we want to be the ones who end it.”

In total Portsmouth are on a 23-game unbeaten run, having gone undefeated in the final 11 games of last season and the first 12 of this league campaign.

On taking inspiration from the Bolton win, Simpson added: “You have to lean on the things you’ve done in the past.

“We’ve just got to approach it in the right way, that’s the only focus we’ve got – making sure we prepare properly, get travelled down there properly and approach the game as positively as we can.”