Avram Grant shouldered responsibility for West Ham's relegation from the Premier League as he paid for the London club's demotion to the Championship with his job.
The Hammers had still to leave the DW Stadium when the club announced Grant had been sacked after his team squandered a 2-0 lead as Wigan, who could yet be relegated themselves, fought back to win 3-2.
All was going well for the visitors after two first-half headed goals from Senegal striker Demba Ba raised hopes of a West Ham 'great escape' against Sunderland at Upton Park this coming Sunday, the final day of the season.
But Charles N'Zogbia gave Wigan hope with a blistering free-kick in the 57th minute before Conor Sammon drew Wigan level.
West Ham then wasted several chances to score the goal that could have boosted their survival hopes before N'Zogbia rubbed salt into their wounds with a stoppage-time winner.
"I'm very sad," said Grant, who dodged questions about what he'd do next after overseeing a second successive relegation from the Premier League following Portsmouth's drop into the Championship last season.
"When I go out from the room I will think about my future," he said.
"The most important for me now is that it's not a good day for the supporters or the club. It's a big club, a good club and I still believe in the future of the club."
Grant tried to do one last favour for his team by taking the blame for the Hammers' plight on "the saddest day" of his 40 years in football.
"Yes, I take responsibility," he said.
"I'm not a guy who gives responsibility to other people, it is my responsibility to pick the team and every game and the tactics so it's my responsibility about the result."
"It's a very sad day, the saddest day since I started football almost 40 years ago."
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 Â£90 million a season in revenue and the likes of England internationals Robert 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 nearby Olympic Stadium once it is revamped as a combined football and athletics venue after the 2012 London Games.
West Ham vice-chairman Karren Brady insisted last week that move would go ahead regardless of whether the club stayed up or not.
Wigan may be second bottom but they are one of five teams in the bottom six who are separated by a point.
And the Latics may well escape joining the Hammers as one of the three relegated sides if they beat Stoke this weekend.
"At half-time we had a real, real mountain to climb," said Wigan manager Roberto Martinez.
"It was a phenomenal game of football and sometimes we say that cheaply but today was unique. It was a unique moment in our history and hopefully we can prepare now for Sunday."