Slaven Bilic has been sacked by West Ham following their poor start to the new season.
The Hammers have won only two of their opening 11 Premier League matches and were defeated 4-1 at home by Liverpool on Saturday.
That defeat has left them in 18th place and Bilic, whose position had come under review twice already this season, has now paid the price for their slow start.
Assistants Nikola Jurcevic, Edin Terzic, Julian Dicks and Miljenko Rak have also left the club with immediate effect, West Ham confirmed in a brief statement which said a new appointment was “expected to be made over the coming days”.
A statement from owners David Gold and David Sullivan read: “During the summer, the board invested heavily signing the players Slaven believed would complete the squad he needed to push the Club back towards the level we had reached in his first season, and we believe we have the players capable of doing that.
Watford vs West Ham
November 19, 2017, 3:30pm
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“Sadly, performances and results have not been of the expected standard and, in recent weeks, we have not seen enough indication of the required improvement to give us the encouragement that things would change and we would meet our Premier League aspirations this season.
“As custodians of the football club it is our responsibility as a board to do what is best for West Ham United, and we believe a change is now necessary to ensure we can begin to move the team back in the right direction.
“We see this as an exciting opportunity to appoint a quality manager to the position to inject fresh ideas, organisation and enthusiasm into a very talented squad.”
Watch highlights here of West Ham 1-4 Liverpool, Bilic's last game in charge
Sky Sports News understands David Moyes has held talks with West Ham about replacing Bilic at the London Stadium, with the former Manchester United and Everton manager having already publicly expressed an interest in the role.
Moyes has returned home to Preston from work as a TV pundit in Doha and remains in pole position to replace Bilic, although negotiations have not concluded and are understood to be continuing.
If Moyes does succeed Bilic at West Ham, his first match in charge is likely to be against Watford at Vicarage Road on November 19, live on Sky Sports Premier League HD.
David Moyes has held talks over the job, according to Sky sources, but Jason Burt thinks West Ham would be taking a huge risk appointing him
Bilic joined West Ham in the summer of 2015 and led the club to their best Premier League points tally in what was their final campaign at the Boleyn Ground, finishing seventh on 62 points and securing a place in the Europa League.
But he was unable to replicate the same success during the club’s first season at the London Stadium, with West Ham failing to qualify for the Europa League group stage and flirting with the relegation places throughout the campaign before finishing in 11th place.
Bilic did lead West Ham to the quarter-finals of the Carabao Cup this season, earning their spot in the last eight with a 3-2 comeback win over London rivals Tottenham, but their failings in the Premier League has ultimately led to his dismissal.