Aberdeen captain Graeme Shinnie has agreed to join Derby County next term.
The skipper, 27, is out of contract at the end of the season and will move to Pride Park from Pittodrie on a three-year deal.
Dons boss Derek McInnes had tried to convince Shinnie to stay, with the Reds making the midfielder-left-back an offer to become the highest paid player at the club.
Derby boss, Chelsea legend Frank Lampard, said: “Graeme will be an excellent addition to our squad for next season and beyond.
“He has been an extremely consistent performer for Aberdeen. He’s someone we’ve watched very closely and we think he will fit into our squad with his ability, attitude and characteristics.
“He has the rest of the season to conclude with Aberdeen but we look forward to welcoming Graeme to Derby County when he reports for pre-season training ahead of next season.”
Shinnie, who is currently sidelined with an ankle injury sustained in a victory over Kilmarnock at Rugby Park, said: “I’m delighted to be joining Derby County and I’m really excited for the challenge.
“I’m looking forward to testing myself in English football and getting the next stage of my career started.
“This is a great opportunity for me to come to a club with such exciting potential as Derby County and I have been impressed with the manager’s plans for the future.”
He added: “I will, of course, remain professional and committed to Aberdeen for the rest of this season as we look to end the season positively. I’ve had a fantastic time at Pittodrie during the last four seasons, made some great friends and loved my football.”
On the Dons, Shinnie – who moved to Pittodrie from Inverness Caley in 2015 – added: “It was a tough decision. A really tough decision.
“The club did everything they possibly could to keep me which was such a good feeling and I appreciate everything the club have done for me over the past four years. The club and the manager have been different class with me, and I can only thank them.
“I love the place. That made the decision that bit harder. I have a great relationship with the manager, one of the strongest I have had. I have a great relationship with all the staff. There are so many people around the club that I get on well with. They have all really helped me. And I have a great relationship with the fans who have been so supportive towards me, ever since I arrived.
“The four years I have had at Pittodrie, I have some great memories but I just felt the age I am at and having a chance to go down to England and play at club who are trying to push to get into the Premier League, this is an opportunity I could not turn down.
“I feel now is the right time for me to go to England and try it down there.”
McInnes is facing a big summer rebuilding job with winger Gary Mackay-Steven – wanted by MLS side New York City – among the other players expected to leave at the end of their deals or loan agreements.
The gaffer said: “Graeme Shinnie confirmed that he will be leaving to join Derby County at the end of the season and while I would obviously have much preferred him to remain here at Pittodrie, I completely respect his decision to make the career decision to try his football south of the border.
“Graeme has been outstanding for Aberdeen Football Club over the last four years and will be a very hard act to follow. I’m sure everyone connected with the club will join me in thanking his for his contribution in his time here and wishing him all the very best for the future. Obviously, we are still hopeful that we can see him make a final appearance in a red jersey at Easter Road next weekend in order that he can say goodbye to the fans properly.”