Norwich City bid around £13.5m for Kalidou Koulibaly back in 2015 but, with Chelsea and Barcelona interested, he's now thought to be worth £40m more.
Southampton failed to get a deal for Kalidou Koulibaly over the line in 2015 - now the Napoli defender is arguably Europe's most in-demand centre-half.
Everton attempted to snap up Kalidou Koulibaly from Napoli last year, Farhad Moshiri has confirmed.
The Newcastle United supremo has been linked with the managerial job at Everton.
Farhad Moshiri refused to sell out for Napoli centre-back Kalidou Koulibaly in 2016 - but he could be a transformative signing for Everton.
Newcastle United fans would love to see Napoli centre-back Kalidou Koulibaly at St James' Park.
Everton made a move for Napoli's Kalidou Koulibaly in 2016 - and may have to renew their interest.
Liverpool reportedly had the chance to sign two brilliant centre-backs this summer but failed to act.
Arsenal are said to be keen on the 26-year-old defender.
Representatives from Tottenham Hotspur and Everton may have had eyes on Napoli's clash with Fiorentina given recent transfer links.