Preston duo Danny Mayor and Jamie Proctor have handed in transfer requests, the club has confirmed.
Mayor was one of North End's leading performers on the wing during a difficult League One campaign and, along with striker Proctor, has expressed a desire to play at a higher level.
"Jamie Proctor and Danny Mayor have informed the club that they would wish to move on to play at a higher level if the opportunity arises," read a club statement. "At the time of writing there has been no interest from other clubs in either of these players and both remain contracted players."
The futures of midfielder Paul Coutts, who was stripped of the captaincy by boss Graham Westley after pondering a transfer request of his own in January, and forward Iain Hume have also been subject to speculation, but the pair will remain with the Lilywhites as things stand.
"Iain Hume and Paul Coutts are both contracted to the club next season," the club statement continued. "There has been speculation regarding offers being made for their services. Again at the time of writing no offers have been received for either player."
The news follows Preston's announcement that 14 players have been released at the end of their contracts, with a further seven transfer-listed as Westley begins his assault on what he has branded "culture of mediocrity" at Deepdale.