West Ham's fate was sealed on the penultimate weekend of the season after a 3-2 defeat at fellow strugglers Wigan Athletic left the Londoners marooned at the foot of the table.
GEAR:West Ham home and away shirts herewith Kitbag. Free delivery on orders over £40
"The club can confirm that Avram Grant is no longer the manager of West Ham United," West Ham said in a brief statement on their website.
Chelsea, whose hopes of retaining their title ended when Manchester United were crowned champions on Saturday, were held to a 2-2 draw by Newcastle United but inconsistent Arsenal lost 2-1 to Aston Villa and cannot now catch their London rivals.
FA Cup winners Manchester City could still finish runners-up but it is an unlikely scenario given their very inferior goal difference. City, though, could still pip Arsenal for the third automatic Champions League place.
Liverpool missed the chance to secure fifth spot and a Europa League place at the expense of Tottenham Hotspur after a 2-0 home defeat to the London side who leapfrogged them into the European position.
Wigan's dramatic victory over West Ham, secured by Charles N'Zogbia's stoppage-time winner after the hosts had battled back from two goals down, gave them a lifeline going into the finale of the season next weekend.
Just one point separates second bottom Wigan (39 points), Blackpool (39), Birmingham City (39), who lost 2-0 at home to Fulham, Wolverhampton Wanderers (40) and Blackburn Rovers (40).
"Everyone at Wigan can be very proud... I hope everyone can be proud of these players next week," Wigan manager Roberto Martinez said looking ahead to next week's clash at Stoke City.
West Ham will start next season in the Championship after their already slim hopes of staying up were quashed by the Wigan revival.
Two goals from Demba Ba had West Ham 2-0 up in the first 26 minutes but N'Zogbia started the comeback with a ferocious free-kick 12 minutes after the restart.
Substitute Conor Sammon made it 2-2 on 68 before N'Zogbia sent the Wigan fans into a frenzy when he won it at the death.
Shortly afterwards West Ham announced Israeli Grant's departure, ending his one season in charge at Upton Park having also been relegated with Portsmouth last term.
Chelsea twice threw away the lead against Newcastle at Stamford Bridge.
Branislav Ivanovic fired Chelsea into a second-minute lead but his strike was quickly cancelled out when Ryan Taylor blasted in a free kick that ricocheted off the shoulder of Jonas Gutierrez and wrongfooted Petr Cech.
Brazilian defender Alex headed home to put Chelsea 2-1 up but Steven Taylor earned Newcastle a point in stoppage-time.
