Goalkeeper Scott Brown will join Aberdeen after 10 years with Cheltenham Town.
The 29-year-old, who has made 287 appearances for the Robins, has turned down a new deal and informed the club that he will join the Scottish Premier League side.
"It was such a difficult decision for me to take," he told Cheltenham's official website.
"I couldn't turn the opportunity down to be involved at a club like Aberdeen and to work with Derek McInnes and Jim Leighton on a full-time basis.
"It's an opportunity that rarely comes around but Cheltenham Town will always be the result I look out for first and whenever I am back I will be watching.
"The fans have been brilliant to me and I have enjoyed every minute of it.
"I am a very ambitious guy and I want to push myself as much as I can and unfortunately that meant leaving.
"It's not something I wanted to do but I want to push myself as much as possible and when this opportunity came along I could not turn it down."