Besiktas president Fikret Orman admits they're keen on Barcelona defender Jeremy Mathieu.
Besiktas have already swooped for Barca teammate Adriano Correia.
"Mathieu is an interesting player," he said, "He's had an interesting career but also has a contract with Barça [until June 2018].
"Until September 2 the transfer market remains open. We're not interested in just one player, there are other alternatives."
"We have good relations with Barça and, well, with all clubs," Orman concluded, "In Adriano's case, it was hard to persuade him to join us.
"Everything was complicated because of the recent coup attempt and his wife was hesitant. In the end, Adriano was convinced by our project."