The Blues confirm on their website that they had parted ways with German coach Thomas Tuchel, who guided Chelsea to Champions League glory in his first season.
Chelsea have sacked manager Thomas Tuchel just seven games into the new season, hours after they suffered a chastening Champions League defeat at Dinamo Zagreb.
The former Borussia Dortmund and Paris Saint-Germain boss leaves Stamford Bridge on Wednesday after a tumultuous period at the club, which included a Champions League triumph.
The English Premier League side said they would move "swiftly" to appoint a replacement, with former Tottenham and PSG boss Mauricio Pochettino and Brighton manager Graham Potter among the early favourites.
"On behalf of everyone at Chelsea FC, the club would like to place on record its gratitude to Thomas and his staff for all their efforts during their time with the club," the Premier League club said in a statement.
"Thomas will rightly have a place in Chelsea's history after winning the Champions League, the Super Cup and Club World Cup in his time here."
The Stamford Bridge club, bought by Todd Boehly's consortium in late May, defended the timing of the decision, which is understood to have been made before the loss in Croatia.
"As the new ownership group reaches 100 days since taking over the club, and as it continues its hard work to take the club forward, the new owners believe it is the right time to make this transition," the statement said.
READ MORE: Paris Saint-Germain fire German coach Thomas Tuchel
Chelsea Football Club part company with Thomas Tuchel.— Chelsea FC (@ChelseaFC) September 7, 2022
Champions League glory
Chelsea are sixth in the Premier League table after three wins, one draw and two defeats in their opening six matches — already five points behind leaders Manchester City
Tuchel, who was in charge for less than 20 months at Chelsea, admitted "everything is missing" after their shock 1-0 defeat on Tuesday.
"Too much to analyse," he said. "I'm a part of it. We are clearly not there, where we need to be and where we can be. So it's on me, it's on us, we need to find solutions."
Tuchel replaced Frank Lampard as Chelsea boss in January 2021, immediately adding steel and focus to the Blues, whose expensively assembled squad were badly under-performing.
The German, 49, steered Chelsea to their second Champions League triumph just four months later, with a stunning 1-0 win over Manchester City in Porto. His contract was extended by two years just days later.
Roman Abramovich announced he was selling the club shortly before he was hit with UK sanctions after the government described him as part of Russian President Vladimir Putin's inner circle.
Boehly's consortium paid a world-record fee of $4.9 billion (£4.25 billion) for a sports franchise to buy Chelsea from Abramovich.
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