Scott Brown is to leave Celtic at the end of the season to become a player-coach at Scottish Premiership rivals Aberdeen.
He has signed a pre-contract agreement to become a member of Stephen Glass' backroom staff, who became manager this week after leaving his head coach role at US side Atlanta United 2 .
"It is a huge decision to leave this magnificent club, which has been such a massive part of my life for so long, but this is a new opportunity for me and a new chapter," Brown told Celtic's website.
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Celtic will never leave me and the club will forever be in my heart.
He added: "The opportunity to join Aberdeen, a club entering an exciting new period with my former team-mate Stephen [Glass] now at the helm, was one I couldn't pass up."
Glass said: "The opportunity to bring a player of Scott's calibre, a leader who has more European appearances for Celtic than any other player, is a huge coup for me and for Aberdeen.
"A born competitor, with a strong appetite to win, his hands-on approach and desire to nurture will hugely benefit the development of the young, emerging talent we have here.
"Scott will be a big part of my coaching team and whilst his impact will undoubtedly be felt on the pitch where I believe he still has much to give, I am looking forward to assisting his transition into coaching."
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