"I am very happy to be coming to Chelsea and the Premier League".
Jorginho has agreed terms over a five-year contract with Chelsea after arriving to undergo his medical ahead of a £57.4m move from Napoli, according to the Evening Standard.
Winning the FA Cup against former Chelsea manager Jose Mourinho's Manchester United in May was scant consolation to finishing 30 points behind champions Manchester City in the league. Chelsea take on Huddersfield Town in their opening fixture of the new Premier league campaign on August 11.
Blues legend Gianfranco Zola is also expected to join the club as Sarri's assistant, after Antonio Conte's reign ended today.
Mahrez and Jorginho were City's two top summer targets, and they now have less than a month to sign a replacement for Yaya Toure, who left on a free transfer at the end of the season.
A turbulent second season on and off the pitch led to the eventual dismissal of Antonio Conte.
With his appointment now confirmed, the 59-year-old Italian said he was looking forward to the challenge of competing for the Premier League crown after Chelsea slipped to fifth last season - having won the title the year before.
Friday's Chelsea statement announcing that they had "parted company" with Conte was brief, and without a thank you, but it did highlight what the club had achieved before relations soured.
"We wish Antonio every success in his future career".