Fresh from whacking seven past Blackburn on Saturday, United were beaten for the first time this season, meekly surrendering their grip on the Carling Cup.
The unlikely figure of Jonathan Spector orchestrated the upset, coming in from the cold on a perishing night of freezing temperatures to score the first two West Ham goals against his old club. Carlton Cole grabbed the others as Sir Alex Ferguson's blood boiled on the touchline.
Four-midable: Carlton Cole celebrates after rounding off West Ham's stunning victory over Manchester United
Victor Obinna was in wonderfultouch, too, creating three of the four as the Hammers completed theirbiggest win over United for 80 years.
Avram Grant even shaded thetouchline fashion stakes, with a claret and blue scarf knotted withRoberto Mancini-like panache alongside Ferguson's bright-red beaniepulled firmly down, perhaps to stop the steam billowing out of his ears.
The United boss was reluctant topile blame on his young players publicly after the defeat but he cannothave been impressed with the way they were muscled out of their stride,even if Luis Boa Morte may have over-stepped the mark with a nastyfirst-half challenge on Fabio.
In touch with fashion? Ferguson braves the wintry conditions with a red hat, while Grant embraces a club scarf
Bebe was hauled off at half-time andJonny Evans was dragged off shortly after being easily beaten for bothof Cole's goals. Wes Brown came on for Evans and promptly fired a passinto touch, under no pressure at all. It was that kind of night.
Robert Green tipped a low shot fromGabriel Obertan onto the post, early in the game, but that was as goodas it got for United. Obinna soon found the net only for the goal to beruled out because it had clipped Spector who had galloped offside.Referee Mark Clattenburg needed the help of his assistant Mike Bull toget it right.
Grant reacted furiously on thetouchline, ranting away in his technical area and, when the ball camehis way, he hurled it furiously in the referee's direction. Clattenburgtook Grant aside for a quiet word.
Two easy: Jonathan Spector fires his second goal past Kuszczak
Moments later, Tomasz Kuszczak waspicking the ball out of his net again and this time it was for real.Spector hurled himself past Darren Fletcher to head Obinna's cross fromthe left inside the post. It was his first goal for the club in 97games, indeed, the first of his career.
He did score against Derby inNovember 2007 but it was later taken from him by the Barclays PremierLeague's dubious panel and went down in the records as an own goal byEddie Lewis.
'Playing in a new position enabledme to get forward a bit more and it was fantastic to score,' said theAmerican, who has spent most of the season in the reserves. This wasonly his third appearance and he is considering a move to Cologne inthe January transfer window. After this performance, manager Grant maywant to veto his departure.
Normally a full-back, Spector was amidfield driving force and the Hammers barely noticed the absence ofScott Parker, struck down by a chest infection but still among thesubstitutes.
Unlikely hero: Spector is congratulated by Victor Obinna
Having waited years for his firstsenior goal, his second came 15 minutes later, when Spector pounced ona loose ball in midfield and drove at the heart of United's shakydefence. He tried to thread a pass into Obinna's feet but it was cutout by Fabio, who slipped making the interception and allowed Spectorto seize the rebound and crash it past Kuszczak.
MATCH FACTS WEST HAM UNITED (4-2-3-1): Green 7; Faubert 6, Tomkins 7 (Reid 74min, 6), Upson 6, Ben Haim 6; Spector 9, Kovac 7; Barrera 5 (Hines 76), Obinna 8, Boa Morte 6; Cole 7 (Stanislas 89). Subs not used: Boffin, Parker, McCarthy,Piquionne. Booked: Reid.MANCHESTER UNITED (4-1-4-1): Kuszczak 5; Fabio 5 (Rafael 65, 5), Smalling 5, Evans 5 (Brown 72, 6), O'Shea 6; Anderson 6; Bebe 4 (Macheda 46, 5), Fletcher 6, Giggs 6, Obertan 5; Hernandez 5. Subs not used: Amos, Park, Carrick, Eikrem.Man of the match: Jonathan Spector.Referee: Mark Clattenburg 6.
The Polish keeper made anotherexcellent low save from Obinna before the break and United were brieflyenergised after half-time. Federico Macheda, on for Bebe, had a sniffof goal when Green made a mistake on the edge of his penalty area butthe England goalkeeper made amends.
Darren Fletcher volleyed over fromthe edge of the box but any hint of a comeback was halted by Cole's twogoals scored from Obinna crosses. First, the West Ham striker leaptabove Evans to glance in a header, then he took a pass into his feet,rolled Evans and fired his second low into the opposite corner.
In keeping with a night of such records, it was the first time Cole had scored twice in a game for eight years.
United were beaten and even surviveda late penalty appeal when John O'Shea seemed to push Zavon Hines offthe ball. West Ham are into the last four of the Carling Cup, one tiefrom their first Wembley final since 1981.
'It is a very, very importantresult,' said Grant. 'First to be in the semi-final is very good and weare trying to build something good, step by step. We played many goodgames without winning and the players lost confidence. But to performlike this against the best team in the country, who could ask for more?'
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