The former Man City star has been on Martin O'Neill's wishlist for some time now and with Pompey yet to appoint a full-time manager Distin may decide to look for a new challenge.
The 31 year old is valued at around £2m and would undoubtedly bring some much needed strength and experience to the troubled Claret and Blue back-line.
Curtis Davies and Zat Knight are unlikely to start the season as first choice centre-backs and towering defender Distin could be the first piece of the transfer jigsaw puzzle for O'Neill.