Keith Curle has urged Carlisle fans to come out in force for their crunch clash with Pompey on Saturday.
The Blues head to Brunton Park keen to close the gap on League Two’s automatic promotion places.
The Cumbrians currently occupy third place in the table with 58 points and boosted their own chances of remaining there with two important wins over Doncaster Rovers and Wycombe last week.
Paul Cook’s side sit six points behind (52) in fifth, but with a game in hand, and know that victory will propel them into the reckoning in the race to go straight up.
The importance of Saturday’s game isn’t lost on Curle.
For Doncaster’s visit to the north west last week, 4,527 witnessed Carlisle win 2-1.
The manager believes it’s important the fans get behind his side for their latest test.
Speaking to the News & Star, Curle said: ‘There’s no excuses now.
‘If you’re a Carlisle United supporter and you’re in your house listening to a radio next Saturday, you’re wrong.
‘Because I don’t care what’s gone on in the past, this is about what we’re trying to do and what we’re trying to bring.
‘I’ll be disappointed if I get people five minutes after the game ringing up with a complaint. It’s because they haven’t been to the game.
‘If you’re a Carlisle fan, come to the game, lend your support.’
Carlisle’s biggest attendance of the season to date is the 7,333 who attended their 3-2 win over Hartlepool back in October.
Last term, when Pompey visited, 5,503 fans were in attendance, with 953 in the away end.
The Blues’ allocation of 1,000 tickets for Saturday’s game sold out last week, with a further 200 offered by the hosts.
Such numbers will ensure a terrific atmosphere at Brunton Park.
But Curle is determined that it’s the home fans who are heard.
He added: ‘If there’s not 9-10,000 supporters there, I don’t know what else I can do.
‘We’re putting the football club in a fantastic position, Portsmouth are going to bring a lot of fans and they are noisy.
‘Their supporters are noisy but they won’t outshout us.’