Bristol Rovers boss Graham Coughlan admitted he’s surprised by Pompey’s poor start to the season.
But he believes the Blues have enough about them – both as a club and as a team – to be in promotion contention come the end of the season.
Kenny Jackett takes his Pompey side to the Memorial Stadium on Saturday, five points and five places worse off than their hosts in the League One table.
Tuesday night's 1-0 victory over Lincoln relieved some of the growing pressure on the manager.
However, with the Blues already 11 points behind league leaders Peterborough and five adrift of Oxford, who currently occupy the final play-off place, they remain some way behind where they want to be.
Jackett’s side still have games in hand on all the teams currently above them in the standings, bar Burton.
But with the ‘financial outlay’ they have, plus ‘a hell of a squad to chose from’, Coughlan is off the opinion that Pompey will come good in the end.
Coughlan told Rovers’ official website: 'Portsmouth are a big club.
'They’re a very, very good team, they're a dangerous team - I don’t think they'll be down there for too much longer.
'I do think you'll probably see them in or around the promotion shake-up at the end of the season such is their squad, such is the financial outlay that they have.
'So, yes, I think they will come good.
'It is, if you're asking me the question, a little bit of a surprise (to see them sitting 16th in the table).
'But it will take time, maybe they're taking time to gel - but they've got a hell of a squad to choose from.'