Besiktas have exercised their option to sign forward Jeremain Lens on a permanent deal from Sunderland.
The Dutchman has been on loan with the Turkish side since the start of the season and, as part of the deal, Besiktas had the right to sign Lens on a full-time contract.
The Turkish Super Lig champions have now taken up that option, and Lens will officially become a Besiktas player on June 1.
Sunderland signed Lens from Dynamo Kyiv in 2015 for £9m and he went on to make 24 appearances, scoring four goals.
The Championship side have recouped £6m from the sale, £1.5m of which was a fee Besiktas paid to take the 30-year-old on loan for the season.
Lens has made 20 appearances since moving to Turkey, and has helped Besiktas into third place in the Super Lig as well as the last 16 of the Champions League.