Pompey are closing in on a versatile defender and also eyeing a central midfielder in a double transfer window swoop.
The Blues boss has just two loans to play with as he attempts to strengthen his threadbare squad.
He will also be hunting for bargains after being handed a small transfer kitty.
And Cotterill has already identified the positions he wants filling.
Pompey's manager is close to landing a defender to bolster a back line which has shipped nine goals in the past three games.
Cotterill has also targeted a central midfielder to help cope with the anticipated losses of Michael Brown and Richard Hughes, who no longer have contracts on the table.
However, the Pompey manager has ruled out bringing in a striker on loan in the belief there are priorities elsewhere.
Cotterill said: 'At least there is now some clarity there for me.
'We know we need to try to find a central midfield player as good or on a par with what we are missing.
'We have got to try to do something maybe in that area, whereas before it would not have been an area I would have looked to strengthen.
'If I can get a flexible defender I would and there is someone I am hopeful of – just hopeful at the moment.
'I have definitely made the contact and that would only be a loan.
'He could play along the back line and probably could play midfield, although not centre midfield.
'He definitely can play both full-back roles and as one of the centre halves. It would depend on who you play him with.
'Although I wouldn't imagine anybody would be coming in here before the weekend or too quickly, really.
'As for a striker, it's on the backburner because I don't think with where we are, we could afford to use another loan for a centre forward.
'I don't think anything will be happening there, I really, really don't think so.'
So far it has been relatively quiet on the transfer front across the four divisions since opening six days ago.
Hull have been the busiest, recruiting Aaron McLean and Matty Fryatt, both of whom featured in Monday's victory over Pompey.
And Cotterill doesn't expect too much action from the majority of the clubs until the end of the month.
He added: 'I certainly don't see anything kicking on until the last week of this window.
'If you can go through the door and stick 1m down for a player it's a bit different. That's probably why Hull ended up beating us on Monday.
'If you have enough money you can sign players and if we were to sign anyone at the moment it would be for a bargain fee.
'I can only see that being somebody who is out of contract at the end of the season.
'The few loans I have enquired about the question comes back: "have you got any money to sign them with?".
'It's not ideal this window. We are where we are and have to be careful with what we do.'