Chelsea midfielder Cesc Fabregas has joined Ligue 1 side Monaco, managed by his former Arsenal team-mate Thierry Henry, on a three-and-a-half year deal.
The 31-year-old Spaniard captained the Blues in the FA Cup against Nottingham Forest on Saturday and was in tears as he applauded fans at the final whistle.
He joined Chelsea from Barcelona in 2014, having played 303 times for Arsenal between 2003 and 2011.
Fabregas described the move as "a new project", calling it a "great honour".
"I'm here to help the team, I'm looking forward to starting. I am very excited," he added.
BBC Sport understands Monaco have not paid a fee for Fabregas but will pay 'bonuses' to Chelsea linked to his performances.
Fabregas won two Premier League titles, two FA Cups and a League Cup in 501 appearances in English football.
Having won six trophies with Barcelona, including La Liga and the Club World Cup, he returned to England to win the Premier League twice in three seasons with Chelsea, first under Jose Mourinho and then Antonio Conte.
In what was the final season of his contract at Stamford Bridge, he had started only one Premier League match under new boss Maurizio Sarri.
Former France and Arsenal striker Henry took charge of Monaco, where he started his playing career, in October - but they have only won twice under his stewardship and are one place off the bottom of Ligue 1 on 13 points from 18 games.
"We are very pleased to welcome Cesc Fabregas to AS Monaco, a world-class player and a great professional, whose arrival demonstrates the ambition of the club," said club vice-president Vadim Vasilyev.
"We are convinced that his experience at the highest level will bring a lot to our players on and off the field."
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