Kenny Jackett has ruled out Pompey getting all their shopping done early when the January window opens.
The Blues are targeting conducting transfer business next month, with several positions identified for strengthening.
Chief executive Mark Catlin has previously revealed the club are searching for players to come straight into the starting XI, rather than bolstering the substitutes’ bench.
However, Jackett insists he will not be rushed into recruiting at the very start of the transfer window.
Instead he intends to monitor the market over the full period as he seeks to bring in the right calibre of performer to aid Pompey’s promotion ambition.
Jackett said: ‘If you can, signing players as early as possible would be great.
‘But, similarly, I think we have to keep our options open right until the end as well, if possible.
‘I don’t think it is the case of signing them all at the beginning, we will see when the right players will become available.
‘You have to wait, but you can also perhaps take a player for a few months on loan, just so you can have a look at him to help you.’
Last January, Andy Cannon arrived two days into the window, signed for an undisclosed fee from Rochdale.
He was followed by Bryn Morris’ arrival from Shrewsbury on January 14, again undisclosed.
However, the bulk of Pompey’s business was conducted towards the window’s end, with four players signed in the final three days.
Firstly, Omar Bogle (Cardiff) and Lloyd Isgrove (Barnsley) were recruited on loan.
James Vaughan (Wigan) and Viv Solomon-Otabor (Birmingham) then landed on the final day, taking the grand total of new faces over the period to six.
Previously under Jackett, in January 2018, the Blues snapped up Sylvain Deslandes and Connor Ronan on loan from Wolves three days into the window.
It wasn’t until the last few days when their recruitment was completed, with Anton Walkes (Spurs) and Stephen Henderson (Nottingham Forest) arriving from January 29 onwards.
Of the eight January loans initiated by Jackett, Walkes remains the only player whose deal has been made permanent.