Kenny Jackett has made recruiting a new left-back his Pompey priority.
And he is unsure whether the existing playing budget will stretch to also strengthening other positions.
The Blues boss wants a specialist left-back to replace the injured Tareiq Holmes-Dennis.
The loanee from Huddersfield is expected to miss around three to four months with the knee problem sustained on the opening day of the campaign.
The departure of Gary Roberts earlier this week has helpfully created space in Jackett’s budget to add to his squad.
However, the only position he is targeting for strengthening has now become the left-back role.
Jackett said: ‘There won’t be many additions between now and August 31. The number will be minimal, and at the moment the priority is a left-back to cover for Tareiq, however long he is out.
‘That is the area we are looking at at the moment.
‘After that the budget is pretty much used up – unless there are any other players going out.
‘I am not sure there are too many more who will go, Michael Smith maybe.
‘A budget always has to be fluid because, as we saw with Tareiq, suddenly somebody is missing for three or four months in what I consider to be a very specialist position.
‘There are some positions you can have a variable player, but I don’t think at left-back you can.
‘As a manager, you are always looking at players anyway.
‘In the centre of midfield I have used Carl Baker in there and we have Danny Rose and then five young players, professionals, who are specialist central midfielders.
‘So we have players in that area anyway.’
– NEIL ALLEN