Manchester United sacked manager Erik ten Hag on Monday after a disastrous start to the season with former Red Devils striker Ruud van Nistelrooy named interim boss.
United dropped to a lowly 14th in the table after suffering their fourth defeat in nine league games at West Ham on Sunday and have won only one of their last eight games in all competitions.
They are also 21st of 36 teams in the Europa League table, having drawn their three opening fixtures.
"Erik ten Hag has left his role as Manchester United men's first-team manager," said a club statement.
"Erik was appointed in April 2022 and led the club to two domestic trophies, winning the Carabao (League) Cup in 2023 and the FA Cup in 2024.
"We are grateful to Erik for everything he has done during his time with us and wish him well for the future."
United added Van Nistelrooy, who returned to the club as Ten Hag's assistant in July, would now serve as interim manager while they went in search of a new full-time boss.
Ten Hag's position had been repeatedly called into question after United co-owner Jim Ratcliffe kept him on board after an internal review at the end of last season when the club finished eighth in the Premier League.
The 54-year-old was even rewarded with a one-year extension of his contract to June 2026 after a shock FA Cup final victory over rivals Manchester City in May.
Former Ajax boss Ten Hag, who joined United in May 2022, had fiercely defended his record in recent weeks after winning two trophies in his two full seasons in charge.
United ended a six-year wait for silverware by beating Newcastle in the 2023 League Cup final.
The Red Devils also reached the FA Cup final and finished third in the Premier League in an encouraging debut season for Ten Hag.
However, the wheels came off in his second season as injuries to key players, the lack of a meaningful impact from big money signings and Ten Hag's failure to implement a clear style of play led to a number of embarrassing results.
United crashed out of the Champions League at the group stage after defeats by Galatasaray and FC Copenhagen, while Bournemouth, Brighton and Fulham were among the other sides to win at Old Trafford in the 2023/2024 campaign.
The implementation of a new sporting structure at United, spearheaded by Ratcliffe, saw widespread change over recent months off the field with the appointment of a new chief executive, sporting director and technical director.
But Ten Hag's surprise victory over Pep Guardiola's all-conquering City side at Wembley in the FA Cup final, saw him handed a stay of execution.
He was further backed in the transfer market with the signings of Joshua Zirkzee, Manuel Ugarte, Matthijs de Ligt and Noussair Mazraoui taking the total spent in his reign to over GBP600 million ($778 million), nearly half of which went on former Ajax players.
Yet, there was no improvement in United's fortunes as Liverpool and Tottenham coasted to 3-0 wins at Old Trafford in September.
Former United captain Gary Neville said Ten Hag had paid the price for an "unacceptable" league position.
"The big shock for me is how bad they've been with the new signings that have come in," Neville told Sky Sports.
He added: "The fact that they are 14th is unacceptable. You can't be in 14th after nine or 10 games with the level of spend that's occurred without being under significant pressure -- and that's what's happened."
Former England manager Gareth Southgate and ex-Barcelona coach Xavi are among the leading contenders to take charge at Old Trafford.
For all Ten Hag's faults, he oversaw just a small period of United's more general decline since legendary former manager Alex Ferguson retired in 2013.
Since the Scot's departure, five permanent managers have now been dismissed without United even challenging for the Premier League title -- a trophy they won 13 times under Ferguson.
