David Moyes is a red-hot favourite to become West Ham's new manager after the club sacked Slaven Bilic.
The Premier League club announced the departure of the Croatian, who was appointed in June 2015 on a three-year contract, on Monday after Saturday's 4-1 loss to Liverpool.
"West Ham United can confirm that Slaven Bilic has today left his position with the club," the Hammers said in a statement.
The club hierarchy "believe a change is now necessary in order for the club to move forward positively and in line with their ambition", the statement added.
"The club's search for a new manager to take West Ham United forward is under way and an announcement regarding Bilic's successor is expected to be made over the coming days."
Former Everton, Manchester United and Sunderland boss David Moyes is Sky Bet's 1/20 favourite to replace Bilic.
He was often linked with West Ham during his successful spell in charge at Everton. However, since leaving Goodison Park four years ago his stock has fallen.
Having replaced the legendary Sir Alex Ferguson, the Scot was always up against it at Manchester United and he failed to last a season. However, he has since also disappointed during jobs at both Real Sociedad and Sunderland, with whom he was relegated from the Premier League last season.
Moyes has already expressed his interest in succeeding Bilic.
"I'm interested, yes," he told beINSPORTS at the weekend.
"I've had no contact from West Ham but I've always said I want to go back into club management. If the right opportunity comes around, I'd be interested."
Former Hammers boss Alan Pardew is next in the betting at 8/1.
Ex-Chelsea and Bayern Munich boss Carlo Ancelotti and Roberto Mancini, currently in charge of Zenit St Petersburg, follow at 16/1.
Bilic's assistants Nikola Jurcevic, Edin Terzic, Julian Dicks and Miljenko Rak have also left the club with immediate effect.
Bilic and co depart with the club in the relegation zone. They sit in 18th place with just nine points taken from their first 11 games. However, they are only one point from safety and just six away from the top half of the table.
Gold and Sullivan said the decision to axe Bilic had been made with "heavy hearts".
In a statement, the club's co-owners said: "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.
"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.
"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."
With Bilic gone, Sean Dyche is the new favourite in the 'next Premier League manager to go' market at 7/4 - a price explained by his position as 13/8 second favourite for the Everton job.
Paul Clement and Tony Pulis come next. Swansea boss Clement is 7/2, while Pulis has been immediately backed in from 8/1 to 4/1. His West Brom side are without a win of any kind since August.
Chelsea's Antonio Conte follows at 9/1. Despite having won the title last season, the Italian has come under pressure with the Blues already well off the pace this term. He has also fallen out with one of the team's star men in David Luiz, who is known to be popular with owner Roman Abramovich. Stoke boss Mark Hughes is also 9/1, and it's 20/1 bar.
West Ham's next manager: The contenders
David Moyes - 1/20
The Scot has been out of work since quitting Sunderland in May but is reportedly in pole position for the Hammers job. Moyes lost 28 of his 43 games in charge of the Black Cats and has won just 47 of his last 137 matches, including his spells at Manchester United and Real Sociedad. His stock has fallen dramatically since he left Everton in 2013 but West Ham could offer him the chance to rebuild his reputation.
Alan Pardew - 8/1
Out of work since being sacked by Crystal Palace in December 2016 - the club were in a relegation fight at the time. Is a former West Ham manager, who took the club to the 2006 FA Cup final but was booted out just over six months later following a poor start to the following campaign.
Carlo Ancelotti - 16/1
It is staggering to think someone of Ancelotti's pedigree is available, but he is. Bayern Munich cut ties with the Italian early in the season and, whoever gets the 58-year-old will get a man to have won three Champions Leagues and titles in Italy, France, England and Spain. The question is, would he fancy a Premier League relegation battle?
Roberto Mancini - 16/1
Previously managed in England with Manchester City, with whom he won the Premier League title - Sergio Aguero clinching the title in memorable fashion with virtually the last kick of the 2012 season. Is currently in charge of Zenit St Petersburg in Russia but is often linked with a return to England. The rescue mission needed at West Ham would be considerably different to the cash-rich situation he found himself in at City though.
Manuel Pellegrini - 18/1
Another Premier League winner. He won the title with Manchester City in 2014 but left when Pep Guardiola became available. He is currently with Hebei China Fortune but, like Ancelotti, is a seasoned winner all over the world.
Chris Coleman - 20/1
Coleman has yet to decide whether to pen a new deal with the Welsh Football Association after Wales missed out on the World Cup. His stock is high after taking Wales to the semi-finals of Euro 2016 and this could be a position to appeal to him.
Sean Dyche - 25/1
Burnley's boss celebrates his fifth anniversary at Turf Moor this month and continues to enhance his reputation as one of the finest English managers around. The Clarets have won promotion, twice, under his watch, and look on course to survive in the top flight for a second straight year after a strong start. That cannot have gone unnoticed further up the pyramid and though West Ham are beneath Burnley currently, their greater potential may tempt Dyche.
Odds correct as at 1200 GMT on 06/11/17.