Maurizio Sarri has left Chelsea to become manager of Serie A champions Juventus on a three-year deal.
Sarri, who joined the Blues from Napoli in July 2018, led them to third in the Premier League and won the Europa League in his one season in charge.
It is understood a compensation fee in excess of £5m has been agreed between the two clubs for the 60-year-old.
Sarri will replace fellow Italian Massimiliano Allegri, who left Juventus at the end of last season.
“In talks we had following the Europa League final, Maurizio made it clear how strongly he desired to return to his native country, explaining that his reasons for wanting to return to work in Italy were significant,” said Chelsea director Marina Granovskaia.
“He also believed it important to be nearer his family, and for the well-being of his elderly parents he felt he needed to live closer to them at this point.”
Sarri signed a three-year deal last July but now becomes the ninth full-time manager to leave Chelsea under Roman Abramovich, who bought the club in 2003.
The Stamford Bridge club are unable to sign any players after being given a two-window transfer ban by world governing body Fifa – a decision they are appealing against at the Court of Arbitration for Sport.
Sarri’s troubles at Chelsea
After earning glowing references for his tactics at Napoli, he looked to have effectively introduced ‘Sarri-ball’ to his new players as Chelsea started their Premier League campaign with a 12-game unbeaten streak.
But the Blues were out of title contention after losing three out of four Premier League games from January to February, including a 6-0 defeat at eventual champions Manchester City, which saw them slip to sixth in the table.
Chelsea then lost 2-0 at home to Manchester United in the FA Cup, when fans booed the Italian’s substitutions and joined in when the visiting supporters sang “you’re getting sacked in the morning”.
However, Sarri remained in charge – and of the 19 matches played after they were beaten on penalties in the Carabao Cup final by Manchester City, his side lost just two, as they won their first European trophy since securing the Europa League in 2012-13.
They also held off the challenge of Tottenham, Arsenal and Manchester United to finish third in the league and clinch Champions League qualification.