Italian giants Napoli are set to demand £110m for central defender Kalidou Koulibaly in the summer window.
According to The Express, via The BBC, Napoli are ready to ask for a world-record fee to prize the defender away from Naples at the end of the season.
The most expensive defender in football history to date is Virgil Van Dijk, following his £75m move to Liverpool from Southampton in January 2018.
Manchester United said to be keen on a deal to sign Koulibaly as they look to strengthen their defence in the summer.
Chelsea have been linked with a swoop for Koulibaly, with Maurizio Sarri having worked with the defender during his time as manager of Napoli.
The Blues have been hit with a two-window transfer ban by FIFA after breaking transfer rules in regards to youth signings.
However, Chelsea have launched an appeal and could yet be able to sign players in the next transfer window.
Alternative centre-back targets
Ake has impressed for Bournemouth this season and could tempt Chelsea into re-signing him.
The Greek defender is one of the best defenders in Europe and would be a great addition to Chelsea’s team.
The Real Madrid centre-back could be tempted by the prospect of regular first-team football.
Stark has been impressive for Hertha Berlin this season and could be ready to make the step up next term.