Skysports.com understands a number of clubs are tracking Brighton defender Inigo Calderon.
The Spanish right-back has been a revelation at Brighton since arriving on a free transfer from Alaves last January.
The 28-year-old, who came close to a move to Southampton last summer, has established himself as a key player in Gus Poyet's side.
Calderon has been instrumental in helping Brighton to the top of League One this season and a host of Championship sides are thought to be keeping tabs on his progress.
Scottish giants Celtic are also thought to be monitoring Calderon with Neil Lennon short of options at full-back.
Calderon, who has popped up with three goals this season, signed a new three-year deal with Brighton last summer and they would be loath to lose the attacking full-back.