Report: Chelsea close to signing Napoli's Koulibaly for €38M

Chelsea's busy summer continues, as the club took a step toward revamping Thomas Tuchel's defense.

The Blues are in advanced negotiations with Napoli to sign center-back Kalidou Koulibaly for €38 million, The Guardian's Fabrizio Romano reports.

The 31-year-old has reportedly agreed to sign a five-year contract worth €10 million per season.

Koulibaly would fill the void left by Antonio Rudiger after the German defender left for Real Madrid this summer on a free transfer. Chelsea also lost Andreas Christensen on a free transfer to Barcelona.

Koulibaly, who has one year left on his Napoli contract, is among a handful of defenders whom Chelsea have been linked to this summer, joining Paris Saint-Germain's Presnel Kimpembe, Manchester City's Nathan Ake, and Jules Kounde of Sevilla.

Chelsea are also close to signing Raheem Sterling from Manchester City and have reportedly shown interest in fellow attackers Rafael Leao of AC Milan and Bayern Munich's Serge Gnabry.

Koulibaly joined Napoli in 2014 and has been a staple in their defense due in part to his durability. He's made at least 25 league appearances in each of his eight Serie A seasons, including 27 last term.

He also helped Senegal win the Africa Cup of Nations for the first time earlier this year.