Tottenham Hotspur boss Mauricio Pochettino has been sacked after five years in charge.
In a statement, the north London club confirmed Pochettino and three members of his coaching team "have been relieved of their duties" following "extremely disappointing" recent results.
Spurs have won just five matches this season and currently lie 14th in the Premier League table.
The club's chairman Daniel Levy said: "We were extremely reluctant to make this change and it is not a decision the board has taken lightly, nor in haste.
"Regrettably domestic results at the end of last season and beginning of this season have been extremely disappointing.
"It falls to the board to make the difficult decisions – this one made more so given the many memorable moments we have had with Mauricio and his coaching staff – but we do so in the club's best interests."
Levy said Pochettino "will always be part of our history" after guiding Spurs to their first Champions League final last season, which they lost to Liverpool.
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Levy added: "I have the utmost admiration for the manner in which he dealt with the difficult times away from a home ground whilst we built the new stadium and for the warmth and positivity he brought to us.
"I should like to thank him and his coaching staff for all they have contributed. They will always be welcome here."
Former Manchester United and Chelsea manager Jose Mourinho is a serious contender to replace Pochettino as Tottenham boss, Sky Sports News understands.
Pochettino's sacking will reignite speculation about his future after the Argentine was previously linked to the manager jobs at Manchester United and Real Madrid.
It will also raise questions about the futures of some of Spurs' star players, including England captain Harry Kane, who have lauded Pochettino during his time at the club.