Kenny Jackett has revealed he is operating under a one-out, one-in transfer policy.
This summer the Blues have recruited Nathan Thompson, Tareiq Holmes-Dennis, Luke McGee and Brett Pitman.
Some of the younger lads may be loaned out as we get towards August because there is no development group hereKenny Jackett
However, players must now depart before Jackett is able to strengthen his squad any further.
The need to drive down numbers – in addition to creating space in the playing budget – means Pompey’s boss is keen to offload.
The names of those up for grabs have already been circulated among clubs.
Jackett is also eager to loan out some of his promising youngsters to generate room in the squad.
And he doesn’t anticipate any more arrivals until there are farewells.
The Blues boss said: ‘Yes, it is a case of one-out, one-in at the moment.
‘In terms of any more players coming in, we would perhaps need players going out.
‘It might not always be direct sales, it might be young players going out on loan. I have inherited quite a big group and for all of those to get games they may have to go out on loan.
‘We are not close to anybody moving or going yet, though.
‘You have to be clear with the players (on their futures), you must speak with them.
‘We are getting towards the end of July, and as soon as August comes with teams getting selected you can see the pattern.
‘Those not playing will be slightly frustrated and I understand them wanting to go and find first-team football themselves.
‘You have to be clear and honest with them. I am sure in terms of the right time and the right player, conversations will come around as we work towards the season’s start, which is within two weeks now.
‘If your training sessions are specific, you need players that are in those particular positions, it’s nothing against anyone else not there.
‘For example, if we are working with Conor Chaplin as a centre-forward, he needs to be integral to the training which is geared towards Saturday.
‘It’s a balance between the two, because treating people unprofessionally isn’t acceptable either.’
The futures of Gary Roberts, Michael Smith and Curtis Main are particularly under scrutiny, having fallen adrift of the first team during pre-season.
Meanwhile, the Pompey manager is seeking to utilise the loan market to benefit his youngsters.
He added: ‘Some of the younger lads may be loaned out as we get towards August because there is no development group here.
‘They have come out of under-18 football and some cannot quite find a place in our first team yet.
‘Bridging that gap with loans can help – both in terms of their progress for the future and also day-to-day managing our numbers.’