Barnsley striker Tom Bradshaw is considering handing in a transfer request according to a source close to the player, with the 25-year-old feeling the club have broken promises to him over his future.
A number of sides have shown an interest in Bradshaw this summer, but Millwall have been leading the chase for his signature.
Barnsley's stance has left Bradshaw frustrated and his relationship with the club's board and manager Daniel Stendel has broken down as a result of the transfer impasse.
HITC Sport understands Barnsley told Bradshaw at the end of last season he could leave this summer and that promises have been broken that they would let him leave should they receive a suitable offer, which they have from Millwall.
Bradshaw is keen to make the move back to the Championship with Millwall, and the striker reluctantly may be forced to hand in a transfer request to try to secure a move if Barnsley do not change their stance and accept Millwall's offer.