Here are 10 of the early contenders being touted to link up with Kenny Jackett's squad.
5. Kean Bryan
A player Pompey have watched in the past. Hasn't featured at Sheffield United and could be a loan option. Photo: Michael Regan
6. Bruno Andrade
Spent time training with Pompey last season and reputation has grown with Lincoln this term. Photo: Paul Harding
7. Paul Downing
Another defender who will be a free agent this summer after leaving Blackburn. Has featured on loan at Doncaster. Photo: Howard Roe / ahpix.com
8. Omar Bogle
A year left on his deal at Birmingham but four goals in eight starts made him one of the more successful January signings Photo: Joe Pepler