The Napoli centre-back was in exceptional form last season and measures in at a whopping 6 foot 5, suggesting he’d be more than suitable to the physical style of the Premier League.
Chelsea and Everton have both been linked with the Senegal international but that interest has seen Napoli’s valuation jump up to an eye-watering £45million – which would make Koulibaly the most expensive Premier League defender of all time.
And in a boost to the Toffees’ transfer plans, that has reportedly forced Chelsea to consider potential alternatives with Lazio’s Stefan de Vrij one of the names in contention.
Injuries limited the Netherlands international to just two Serie A appearances last season but he thoroughly impressed at the 2014 World Cup and produced strong form during the 2014/15 campaign.
Mirror Football believe De Vrij could be available for just £15million this summer – a third of the price they’d have to pay for Koulibaly.