The Black Eagles recently signed Barcelona full-back Adriano and have built close ties to the La Liga giants over the past few years.
The Istanbul giants want to bolster their defensive line after winning the league title and booking a place in the Champions League.
Despite winning the Super Lig title last season, Besiktas conceded the highest number of goals in the top three.
“Mathieu is an interesting player,” Orman stated in a recent press conference, “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.”
Turkish sports newspaper Fanatik claim that Besiktas are already in talks with Mathieu and that they have offered a one-year loan deal.
The report claims that Barcelona want €7 million for Mathieu and that Liverpool like Besiktas are working on strengthening their defence this summer following a number of departures and injuries.
Barcelona have reportedly given the experienced defender the green light to leave this summer after signing Samuel Umtiti and Lucas Digne.