Sky Sports understands a number of clubs are weighing up moves for Carlisle striker Francois Zoko.
The Ivorian is out of contract in the summer and as yet no new deal has been agreed at Brunton Park.
The news has alerted a host of sides to Zoko's possible availability on a free transfer at the end of this season.
Zoko has established himself as a key player at Carlisle since arriving in the summer of 2010 and he has netted 12 goals this term.
League One champions-elect Charlton are thought to be admirers of the versatile forward and are ready to make a move for Zoko this summer.
Rangers are also thought to be keeping tabs on Zoko and, with the African available on a free transfer, he would fit their bill for potential signings this summer because of their financial problems.