Kalidou Koulibaly to Chelsea transfer set to cost Napoli manager his job after 'serious threat'

Chelsea's pursuit of Napoli defender Kalidou Koulibaly could result in Luciano Spaletti resigning from his role as manager of the Italian club.

The Blues have been linked with a number of defenders this summer including Inter's Milan Skriniar, Sevilla's Jules Kounde and Torino's Gleison Bremer. Following the departures of Antonio Rudiger and Andreas Christensen, Chelsea are a little light at the back in terms of central defensive options.

Koulibaly only has a year left on his current deal with Napoli and is attracting interest from the likes of Chelsea, Juventus and Barcelona. The 30-year-old contributed heavily to Napoli's defensive efforts last season, boasting the joint-best defensive record in Serie A after conceding just 31 goals in 38 games.

Spaletti will reportedly resign if Napoli are to cash-in on Koulibaly this summer, according Sport via Italian outlet Corriere dello Sport. The Italian outfit have already let go of club legend Lorenzo Insigne this summer following the winger's decision to join MLS side Toronto on a free transfer.

The Senegalese international has been at the club for eight years and is one of the key players in Spaletti's squad. President Aurelio De Laurentiis admitted that the club cannot force Koulibaly to stay, regardless of how much the club would like him to remain in Naples.

De Laurentiis said: "He is a symbol of Napoli, and if he wants to no longer be a symbol, he must decide. We must decide.

"We want Koulibaly to stay, but people can't be forced to stay. Everyone has their own dignity and needs, we respect everyone."

Napoli finished third in Serie A last season but the Italian club could be set for a summer of change with Insigne leaving and Koulibaly being sought after by Europe's top