Scott McKenna has handed in a transfer request in a bid to force an Aberdeen exit.
Sources have confirmed the latest development in the saga surrounding the stopper’s future.
Offers of around £3 million for the Scotland international centre-back – from England Championship sides QPR and Nottingham Forest – have been rejected during the transfer window so far.
Last summer, Aston Villa saw a bid of £6.5m for the 22-year-old knocked back.
It is thought a bid of around this figure would be required again to convince Pittodrie chiefs to part with one of their most valuable assets. The English transfer window closes on Thursday at 5pm.
It is unclear whether McKenna will be on the Dons’ flight to Croatia on Wednesday, where they are due to take on HNK Rijeka in the Europa League third qualifying round first leg. That game kicks off at 6pm on Thursday.