Tom Kilbey could make his Pompey bow at Watford.
The 20-year-old midfielder has recovered from the knee injury that he picked up in pre-season.
And his former club Millwall are prepared to negotiate on the 50,000 payment that Pompey would have to make if he makes his debut.
Blues boss Steve Cotterill explained: 'Tom is a young player who was bought from Millwall for so much money, and if he played a game it would trigger a payment.
'He got injured in pre-season so I saw him for only one game.
'He's been back training for a while now and we might see him at Watford.
'There might be some sort of deal done but until I can physically see that deal, we will have to wait and see.
'Millwall have been pretty good about it. They don't want to hinder the boy's progress so have wiped a chunk of it, but there would still have to be money paid for appearances and his own contract would have to be settled.'