A statement from the club read: "Chairman Bill Kenwright, the board of directors and major shareholder Farhad Moshiri would all like to express their gratitude to Ronald for the service he has given to the club over the past 16 months and for guiding the club to seventh place in last season's Premier League campaign."

Koeman led the club to a seventh-placed finish last season, his only full campaign at the helm after arriving from Southampton, but has had a torrid time of late.

Two home defeats in four days, 2-1 to Lyon in the Europa League and 5-2 against Arsenal on Sunday, and the chorus of boos that followed each time proved the end of the line for 54-year-old.

The departure of Romelu Lukaku, who joined Manchester United for £75million in the summer, left the Toffees light up front but Everton's use of those funds has been questioned.

Gylfi Sigurdsson and Davy Klaassen cost almost £70m between them and Wayne Rooney was brought back from Old Trafford on a high-profile free transfer but Lukaku was never adequately replaced.

A further £55m was spent on goalkeeper Jordan Pickford and defender Michael Keane, yet the Toffees have conceded 18 goals in nine league games and only rock-bottom Crystal Palace have a worse goal difference.