Sunderland winger Jeremain Lens is poised to join Besiktas after the clubs agreed a £4.5million fee.
The Turkish club, who signed Alvaro Negredo from Valencia on Wednesday, have also added Real Madrid defender Pepe this summer.
Sunderland rejected an offer from Besiktas to take Lens on an initial loan earlier in the window but they have now agreed on terms with the 29-year-old due to sign a three-year deal.
Lens managed only 25 appearances for the Black Cats since joining from Dynamo Kyiv back in 2015.