Scott McKenna is close to finalising a move that will take him from Aberdeen to Nottingham Forest.
The Scottish Premiership side confirmed on Sunday that a "significant offer" had been received for the centre-back, which BBC Scotland has learned came from the English Championship club.
McKenna, 23, handed in a transfer request in August 2019 with Aberdeen rejecting bids from several clubs.
The player was left out of the squad for Sunday's visit of Motherwell.
Aberdeen boss Derek McInnes told BBC Radio Scotland that McKenna, capped 16 times, had not been included while negotiations were ongoing.
"We're close, the clubs have been speaking," he added. "From our point of view, I prepared for a team without Scott in it yesterday. It's seems to be edging a bit closer to the clubs agreeing."
Asked whether a fee had been agreed, McInnes replied: "Not as far as I'm aware, but talks are encouraging. There's been interest for a while from that particular club but it has gathered momentum in the last 24 hours."
'A matter of time' - analysis
Former Aberdeen captain and manager Willie Miller on BBC Radio Scotland
It may be welcomed by the club financially as they have put a lot of funds into supporting the manager.
I always thought he would go down south. He is tailor-made for the Championship or Premier League. It was only a matter of time.
The requirement is to balance the books and it's great news for the development programme at Pittodrie. They turned down a big offer from Aston Villa in 2018 as the timing wasn't right.
Scott has been a great servant over the short period he has been there.