Pompey are looking to complete the signing of Shrewsbury keeper Craig MacGillivray.
And a deal could be sealed as early as Monday, as Blues boss Kenny Jackett looks to complete his third signing of the summer.
MacGillivrary, who moved to New Meadow on a free transfer from Walsall last year, is once again out of contract.
The 25-year-old has been offered a new deal by the Shrews but featured only 14 times last season as he played back-up to Manchester United loanee Dean Henderson.
It is understood he is keen to play regular first-team football and would arrive at Fratton Park to battle it out with Luke McGee for the No1 spot.
As revealed by The News yesterday, Jackett is also closing in on a permanent deal for Anton Walkes, who spent the second half of last season on loan at Fratton Park.