Jake Jervis and Thery Racon have both been released by Pompey.
The news comes as the Blues announce their retained players’ list for next season.
Jervis and Racon will depart, along with defender Marcos Painter, as nine players leave Fratton Park.
But Andy Awford has taken up an option to keep striker Ryan Bird at the club.
He will be joined by Adam Webster, although fellow home-grown talent Ashley Harris is on his way.
Yassin Moutaouakil has also been released, along with Phil Smith, George Branford, Liam Triggs and Josh Warren.
Of the out-of-contract players, talks are continuing over new deals for Jed Wallace, Bondz N’Gala, Nicky Shorey, Jack Maloney and Nick Awford.
The same will be expected for Trevor Carson and Danny Hollands after their loan deals end.
Dan Alfei and Michael Drennan also see their temporary agreements come to a close.
All other senior players are under contract.
From the existing Academy set-up, Ben Close and Bradley Tarbuck have been offered first-year professional contracts.
Harry Medway, Lewis Horsburgh and Kim Jae-Heon depart.
Out of contract with talks continuing
Options taken up
First-year pro contracts
Released from Academy
Kim Jae Heon