English website Goal, as quoted by The Sun, is reporting that Sarri has his sights set on bringing Koulibaly to Stamford Bridge.
The same article states that the former Napoli boss will have to convince Chelsea FC to part with a transfer fee in the region of £88m to sign the Senegal international.
According to the same story, Arsenal and Chelsea FC have both made attempts to sign Koulibaly from the Serie A giants in the past but Napoli have been reluctant to sell.
Goal go on to claim that Chelsea FC are at the front of the queue to sign the African centre-half from the Serie A runners up in the current transfer window.
Koulibaly scored five goals in 35 games in Serie A last season, including a dramatic winner in a 1-0 victory over Juventus in Turin at the end of the 2017-18 season.
Chelsea FC are looking to rebuild their squad after the Blues finished in fifth spot in the Premier League last term to miss out on a Champions League spot for the second time in three seasons.
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