Names including Kyle Joseph, Aaron Collins and Matt Butcher have all been thrown into the rumour mill, alongside long-term targets Kyle Wootton and Will Boyle.
Danny Cowley has continued to pursue deals for Hayden Carter and 2021-22 top-scorer George Hirst to return to Fratton Park following their successful loans last term.
Yet, the Blues have completed just one signing to date, with Marlon Pack arriving on a two-year deal from Cardiff last week.
Meanwhile, as the transfer window ticks on, a number of those 25 names have found new homes away from Fratton Park.
Indeed, 11 have found themselves alternative destinations or signed new deals to stay at their respective clubs.
We’ve taken a look at where those names have ended up since their links to PO4.
Here’s what we found.
9. Lynden Gooch - Sunderland
The versatile Sunderland star was eyed by Cowley ahead of the transfer window as Marlon Romeo’s replacement at right-wing back. The Blues were also joined by Swansea with the pair both keen to land the American, who was out of contract at the end of the season. However, the 26-year-old agreed fresh terms at the Stadium of Light, putting to bed any potential move away from the north west this summer. Photo: George Wood
10. Callum Wright - Leicester
The News revealed at the end of May that the Leicester youngster was on Cowley’s radar following two successful loan spells at Cheltenham. Pompey also joined the Robins in pursuing a move for the midfielder, who was also linked with Plymouth and Luton. However, a deal could now prove more challenging with Wright penning a new 12-month deal to remain at the King Power Stadium. Photo: Matthew Lewis
11. Toby Mallarkey - Altrincham
The central defender was at the centre of gossip linking him with a possible move to Pompey. However, the Blues’ efforts were quickly put to bed with the 26-year-old signing a fresh deal to remain at Altrincham soon after the club were credited with a link. Photo: Alex Livesey