Napoli have fired a warning to any clubs interested in signing Kalidou Koulibaly by insisting that he's not for sale, although head coach Carlo Ancelotti has confirmed his €150 million (£130m/$169m) release clause.
That isn't due to kick in until 2021, with Koulibaly having signed a new deal with Napoli back in September 2018 that will tie him to the club until 2023.
The 27-year-old has been linked with the likes of Manchester United and Chelsea although it appears it will take a huge bid for the Naples club to even consider a sale.
Ancelotti told Tuttosport: "The best centre-back in the world? Yes. And he has more room for improvement. He's worth €150 million and he is non-transferable.
"Koulibaly's contract will expire in 2023. In 2021 he will have a €150 million release clause, but Napoli do not need to sell, the president does not want to sell and the question does not arise."
The Senegal international is preparing to face Arsenal in the Europa League on Thursday, with the Gunners 2-0 ahead in the tie courtesy of goals from Aaron Ramsey and an own goal from Koulibaly.
The first leg was, however, marred by allegations of racist abuse towards the centre-back that has seen Arsenal confirm they are investigating the video that appeared on social media.
That came after more reports of racist abuse in Italian football, with Juventus duo Moise Kean and Blaise Matuidi having suffered alleged abuse by Cagliari fans.
And Ancelotti expressed his dismay at the situation, urging those supporters that are behind the accusations to stop.
He added: "I was speechless. It's unacceptable. Intolerable. Chants against Koulibaly, Kean and Matuidi, insults to [Sinisa] Mihajlovic when he returned to Florence. Enough. Enough. Enough. Enough. Enough.
"It is no longer possible to conceive football in this way. This is not the football we love."
Napoli are currently 17 points behind Juventus in the Serie A table although are on course to secure their place in the Champions League next season, with them being seven points ahead of third-placed Inter and a further five clear of AC Milan.