Carlo Ancelotti has left Everton to become head coach of Real Madrid for a second time.
The 61-year-old Italian, who managed Real Madrid for two years between 2013 and 2015, has left Everton after 18 months in charge at Goodison Park.
He succeeds Zinedine Zidane at Real and the move leaves Everton searching for a sixth permanent manager in five years.
Ancelotti has signed a three-year deal at Real and said the move represented "an unexpected opportunity".
He added: "I have complete respect for everyone associated with Everton and hope they can achieve the exciting opportunities they have in front of them.
"While I have enjoyed being at Everton I have been presented with an unexpected opportunity which I believe is the right move for me and my family at this time."
Real will present Ancelotti to the media on Wednesday, while Everton said they "will begin the process of appointing a new manager immediately".
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'A brutal truth' - analysis
Phil McNulty, BBC chief football writer
Everton will have been left stunned by the speed of developments in the last 24 hours as owner Farhad Moshiri's "Hollywood" manager leaves.
Ancelotti's arrival was regarded as a real coup by Moshiri, persuading one of the game's most decorated and respected figures to come to Merseyside to restore Everton to former glories.
The 61-year-old's reign has been a mixed bag with dreadful home form balanced out by results like their first win over Liverpool at Anfield since 1999 - but ultimately a 10th-place finish in his first full season was a disappointment.
Ancelotti, however, was still held in huge regard by Everton supporters, who have been left bitterly disappointed by his decision to depart.
The brutal truth is that for all Moshiri's finance and ambition, Everton still cannot regard themselves as anywhere near the elite, which always makes them vulnerable to clubs such as Real Madrid setting sights on their prize assets.
The usual suspects are being linked, such as Eddie Howe after he turned down Celtic, former Wolves boss Nuno Espirito Santo and ex-Everton boss David Moyes - although that is unlikely to happen after he verbally agreed a three-year deal at West Ham after taking them into Europe. Moshiri, though, is something of a wildcard and may have ideas of his own.
|'Carlo Fantastico' - did you know?|
|Of managers to have taken charge of at least 10 Premier League games with Everton, their average of 1.53 points-per-game under Carlo Ancelotti is better than under any other previous boss. David Moyes sits second on 1.5|
A man to overturn Real's woes
Ancelotti has won 15 major trophies during his career and is one of only three managers to win three European Cups - along with Liverpool legend Bob Paisley and former Real boss Zidane.
The Italian has domestic titles with AC Milan in his homeland, Chelsea in England, Paris St-Germain in France and also in Germany with Bayern Munich.
Having previously won the Champions League twice with Milan, he guided Real Madrid to a landmark 10th success in the competition in 2014 but departed as manager a year later.
Real won the Champions League three times under Zidane but ended the 2020-21 campaign without a trophy, having finished second in La Liga behind city rivals Atletico Madrid.
|Five years of change at Everton|
|Carlo Ancelotti||June 2020||43.1|
|Marco Silva||December 2019||35.8|
|Sam Allardyce||May 2018||37.5|
|Ronald Koeman||October 2017||40.4|
|Roberto Martinez||May 2016||38.1|
'I know Rafa would take it'
Ex-Liverpool defender Jamie Carragher has been quick to state his former manager Rafael Benitez - who lives on Merseyside - is an obvious choice for the Everton job.
Spanish football expert Guillem Balague told BBC Radio 5 Live: "Could Rafa Benitez do the job at Everton? I know for a fact he would take it.
"Real Madrid were waiting for Mauricio Pochettino. Paris St-Germain triggered a renewal of his contract. So the only way for Pochettino to go to Real or Spurs is to publicly say 'I'm leaving'. So that meant Real had to see what is out there.
"It's a team that has players Ancelotti had in his time there. Florentino Perez decided to sack him having won the Champions League, he felt the team wasn't working hard enough.
"Luka Modric and Sergio Ramos were asked about him and they said 'keep him'. He got sacked, the relationship with Perez went sour earlier on and wasn't great.
"But we reach a moment where Real Madrid need someone that can bring a happy face to the camp and exploit a mixture of youth and veteran figures."
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