Although, he believes it could be a recruitment scenario focusing on one in and one out at Fratton Park.
The Blues have signed eight players during a busy summer, including substantial fees paid for John Marquis, Marcus Harness and Ellis Harrison.
In addition to those arrivals, it is understood Pompey are also monitoring Liverpool’s Herbie Kane.
The midfielder enjoyed an impressive season-long loan at Doncaster last term – and has once more been made available.
And, speaking generally, Jackett admitted there could be one other fresh face ahead of the September 2 deadline for League One and League Two clubs.
Pompey’s boss said: ‘We will see what happens (about signings), I don’t think much is going to happen.
‘Jamal and Louis wanted moves – and I wish them all the best – and the day before John Marquis came in.
‘So from that day it has been about getting the best from the squad you’ve got – ensuring I make the right decisions, find the right balance and give people the right opportunities.
‘But, similarly, I wouldn’t rule out anything else necessarily happening, I don't know, but I think it will be minimal, if anything.
‘Things can change, but I would suggest one in, one out, that’s how it looks at the moment.
‘I’m working hard with the group we have and hopefully they can respond, I am sure they can.
‘It’s exciting for me as a manager, I’m looking forward to seeing how people develop and how the team do.’
Jackett has calculated he currently possesses a first-team squad of 23.
It’s a figure he doesn’t believe gives him excessive numbers.
He added: ‘We haven’t got a stupid amount of numbers.
‘Matt Casey, when he gets fit, will go out on loan – so that will be him and Adam May. Then Jack Whatmough has a long-term injury and certainly won't play the first half of the season.
‘After those guys, there are 23 players and three of those are keepers – so 20 outfield players for 16 positions.
‘Plus, we have two or three injured, so it’s not like we’ll have 3-4 in the stand all the time, they will all be close.
‘At Shrewsbury it quite naturally fell into 19 fit players, while Birmingham in the Carabao Cup was a natural 17 out of the group, then you can supplement it with a youngster.’