Joe Gallen has admitted Pompey belief is flourishing.
The unbeaten Blues are top of the table following Saturday’s 2-1 triumph at Peterborough.
The Posh had topped League One ahead of the clash, yet were floored by second-half goals from Oli Hawkins and Jamal Lowe.
Many of the 2,513 away supporters present remained to celebrate at London Road long after the final whistle, before moved on by stewards.
Inevitably there is growing conviction among the Fratton faithful this season could yield promotion to the Championship.
Gallen points to the campaign being just eight games old as justification for remaining grounded.
Yet he concedes belief among players and supporters is noticeably escalating.
The Blues’ assistant manager said: ‘There seems to be belief there, you can sense it very early on from the sheer amount of fans we had for this game.
‘Peterborough was not quite a big game, but did have the feel of a big game – and you can sense from the supporters they are picking up some good vibes from the team and the results are coming.
‘There’s some belief, there is some belief forming, but let’s get onto the next game,
‘I think you can sense from the players they really believe in themselves as it is, but you have got to look for that word (promotion) in March, you’ve got to look for that word in April, we have to make sure we are in the mix.
‘I cannot say that word (promotion) because it is miles away and we have a lot to do, but some belief is forming.
‘My point is you can sense from the fans that the belief is forming and if they are seeing something you can’t fool any punters, you can’t fool any supporters.
‘They know and they have a feeling that we could be in for a good season.’
Pompey are now five points clear of third place after results went their way at the weekend.
Meanwhile, defeats for Barnsley, Sunderland, Walsall and, of course, Posh, ensure Kenny Jackett’s men are the sole undefeated side in League One.
He added: ‘You just have to roll to the next game, see if any injuries have been picked up and we approach a very difficult game against Wycombe.
‘There will be an expectation and they are not going to make it easy for us, they’re going to make it tight, get behind the ball and make it very tough.
‘Hopefully we'll play well, show patience, and get there in the end.’