Brentford would want £2m plus add-ons to sell defender Harlee Dean.
The centre-back, who is in the final year of his contract, is of interest to Sheffield Wednesday, Hull City and Leeds United.
Dean, 26, has discussed a new deal at Griffin Park but is waiting to see whether a club comes in for him before making a decision on his future.
Boss Dean Smith has said Dean will not regain the captaincy unless the player signs a new deal.
Dean missed the Bees’ opening Championship game at Sheffield United through suspension but played in the EFL Cup in midweek and is available for Saturday’s game against Nottingham Forest.