Here are 10 of the early contenders being touted to link up with Kenny Jackett's squad.
1. Ryan Pryce
Pompey along with Hull and Fleetwood said to be interested in the 20-year-old Cardiff full-back.
2. Jordan Willis
Central defender is highly regarded at Coventry but is out of contract and set to leave. Championship clubs like Hull and Derby also said to be keen.
Photo: David Davies
3. Viv Solomon-Otabor
Kenny Jackett has made it clear he's interested in a move for the out-of-contract Birmingham man, who's been on loan at Fratton
Photo: Joe Pepler
4. Tom Lockyer
Defender is sought after as he leaves Bristol Rovers and Kenny Jackett is keen - but so are Championship clubs
Photo: Robin Jones/Digital South