Wigan - Avram Grant was sacked as West Ham United manager on Sunday in the aftermath of the club's relegation from the Premier League, with the Israeli describing it as the saddest day of his 40-year career.
"The club can confirm that Avram Grant is no longer the manager of West Ham United," said a statement released on the club website.
"First-team coach Kevin Keen will take charge of the team for the final home match of the season against Sunderland on May 22."
The east London club's owners David Gold and David Sullivan, together with vice-chairwoman Karren Brady, acted swiftly after watching West Ham relegated as Grant's team squandered a two-goal lead in their 3-2 defeat at fellow strugglers Wigan.
With only one league game to play, West Ham - who sit bottom of the table and six points from safety - are condemned to play in English football's second tier for the first time since 2006.
They had led through two goals from Demba Ba, but Charles N'Zogbia led Wigan's fightback and scored twice including a 90th minute winner after a mistake from Hammers goalkeeper Robert Green.
Gold, Sullivan and Brady were at the DW Stadium and called Grant into a meeting less than an hour after the final whistle to announce that the Israeli would be sacked.
Speaking at his post-match press-conference, Grant said: "It is a very sad day for me, I think the most sad day since I started in football almost 40 years ago.
"I came (to the club) with a lot of desire and belief that we could do something here.
"I knew the financial problems and that the team was saved from relegation because the league was weak last year.
"I still thought that we could do better, but maybe this game is the story of our season."
The financial cost of relegation will be huge for West Ham, who already reportedly have the eighth highest wage bill in the Premier League.
Top-flight football is worth around 90 million a season in revenue and the likes of England internationals Green, Scott Parker, Carlton Cole and Matthew Upson are all likely to be sold to make up some of the short-fall.
West Ham are also due to move from Upton Park to the Olympic Stadium once it is revamped as a combined football and athletics venue after the 2012 London Games.
Brady this week insisted that move would still go ahead regardless of whether West Ham stayed up or not.
Grant's sacking marks the end of another depressing league campaign for the former Chelsea boss, who had taken charge at Upton Park last year after leaving Portsmouth in the aftermath of their relegation from the Premier League.
But Grant, who was handed a four-year contract to replace Gianfranco Zola, endured a miserable season from start to finish and his relationship with his employers quickly became strained as West Ham struggled to climb away from the relegation zone.
Although he led the Hammers to the League Cup semi-finals and the FA Cup quarter-finals, Grant won just seven of his 37 Premier League matches this season.
It was reported that West Ham offered Grant's job to Martin O'Neill in January but the former Aston Villa manager rejected their approach.
Grant's side briefly sparked hopes of avoiding the drop when they won three of five Premier League games from February 2 to March 5, including a memorable 3-1 home victory over Liverpool.
But the loss at Wigan was a sixth in seven league matches and Grant was always likely to pay the price.
QPR manager Neil Warnock could be a potential replacement for Grant, while former Newcastle and Blackburn boss Sam Allardyce would be another candidate.