Skysports.com understands a host of clubs are chasing Colchester defender Marc Tierney.
The 25-year-old's contract expires at the end of the season and as yet no new deal has been agreed.
The news has alerted a number of sides to his possible availability for a cut-price fee in January or for free next summer.
Tierney, who started his career at Oldham, has established himself as a key member of the Colchester side since signing permanently in January 2009 after a successful loan spell.
Preston are believed to be one of the sides keeping tabs on Tierney's situation with the club holding a long-term interest in the left-back.
Former Colchester boss Aidy Boothroyd could also move for Tierney with the Coventry chief a big admirer of the player.