West Ham hammered Blackpool to return to the top of the Championship despite having to play for 35 minutes with midfielder Henri Lansbury in goal.
Substitute Lansbury was forced to don the gloves after Robert Green was dismissed for a foul on Roman Bednar.
At that stage United led 2-1, with James Tomkins and Nicky Maynard scoring for the visitors before Kevin Phillips pulled a goal back for Blackpool.
United sealed a great win with goals from Gary O'Neill and Ricardo Vaz Te.
It is a real testimony to West Ham's promotion credentials that despite their numerical and personnel disadvantage they were still able to comfortably overcome a Blackpool side that had gone seven matches unbeaten before this game.
Ian Holloway's side looked a shadow of the side of recent weeks, but this should take nothing away from the Hammers.
Prior to what could, and probably should have been a game-changing red card incident in the 53rd minute, Sam Allardyce's men had dominated.
They seized control of the match during a four-minute spell in the first half, during which Tomkins headed home Mark Noble's free-kick and Maynard converted Joey O'Brien's cut-back for his first West Ham goal since joining in January.
Desperate for a foothold in the game, Holloway sent on Kevin Phillips and the veteran striker gave his side just that in first-half injury time, nodding home Alex Baptiste's speculative cross.
The contest was seemingly thrown wide open eight minutes after the break when Green was sent off after chasing rashly from his line to bring down the onrushing Bednar.
However, West Ham - who had not named a goalkeeper among their substitutes - were largely untroubled after that as emergency goalkeeper Lansbury was shielded superbly by his defence.
The visitors gave themselves breathing space with just over 15 minutes to go when O'Neill lashed a crisp 20-yard drive into the bottom corner after Winston Reid's effort from Vaz Te's corner was blocked by Stephen Crainey.
Phillips rattled the inside of the post with a lofted volley for the home side before Vaz Te put the result beyond all doubt when he raced clear to open his own Hammers account with a neat finish.
Blackpool manager Ian Holloway:
"It was pretty horrendous from our point of view. Only one team turned up. In every single way they were better than us.
"They were more professional than us, they played it in the right way on a difficult surface and we just made mistake after mistake after mistake.
"Just about everything that could go wrong did. I felt my lot were caught in the emotion of it. They were not professional, they did not get it right and we were beaten by a better team."
West Ham manager Sam Allardyce told BBC Radio 5 live:
"The outstanding quality from my players was there in abundance. That was a remarkable achievement, a remarkable performance and a remarkable result.
"From the very, very start we controlled the game. We have come out with a huge amount of credit with our display.
"Three games on the trot we've now been reduced to 10 men and we've won two and drawn one. It is the unfortunate ruling by the bosses at the league, which I thought was outrageous at the time, to reduce the substitutes from seven to five.
"That ridiculous decision has caused a lot of us managers to not put a goalkeeper on the bench. We took the gamble and it paid off because Henri Lansbury was outstanding in goal."
Live Text Commentary
Full Time The final whistle goes and the game is over.90:00 +5:27
The ball is crossed by Ian Evatt, clearance made by Winston Reid.90:00 +4:50
Jack Collison has a drilled shot. Matthew Gilks makes a save.90:00 +1:07
Matt Phillips takes a shot. Save by Henri Lansbury.89:43 Goal scored
Goal! - Ricardo Vaz Te - Blackpool 1 - 4 West Ham Ricardo Vaz Te scores a goal from inside the penalty box to the bottom left corner of the goal. Blackpool 1-4 West Ham.88:59
Inswinging corner taken by Matt Phillips from the left by-line.88:38
Matthew Gilks takes the free kick.88:38 Booking
Booking Gary O'Neil shown a yellow card.88:05
Carlton Cole is ruled offside.87:38
John Fleck takes a shot. Blocked by James Tomkins.86:49
The assistant referee flags for offside against Kevin Phillips. Henri Lansbury takes the indirect free kick.85:20
Alex Baptiste sends in a cross, clearance by George McCartney.82:52
Barry Ferguson delivers the ball.80:59
Henri Lansbury restarts play with the free kick.80:59 Substitution
Substitution Carlton Cole replaces Nicky Maynard.80:59
Kevin Phillips produces a lobbed right-footed shot from outside the area and hits the bar. Roman Bednar is caught offside.80:01
Nicky Maynard produces a right-footed shot from the edge of the area and misses to the left of the goal.79:08
Ian Evatt crosses the ball, clearance made by Ricardo Vaz Te.78:08
John Fleck takes a shot from a long way out clearing the bar.77:59
A cross is delivered by Alex Baptiste, Winston Reid makes a clearance.
Effort from outside the penalty box by Kevin Phillips goes wide left of the goal.75:31
Centre by Alex Baptiste, Henri Lansbury makes a save.73:53 Goal scored
Goal! - Gary O'Neil - Blackpool 1 - 3 West Ham Gary O'Neil gets on the score sheet with a goal from the edge of the penalty area to the bottom left corner of the goal. Blackpool 1-3 West Ham.72:46
Ricardo Vaz Te delivers the ball, blocked by Alex Baptiste. Corner taken right-footed by Mark Noble from the left by-line, James Tomkins takes a shot. Clearance by Stephen Crainey.72:08
Winston Reid restarts play with the free kick.72:08 Booking
Booking John Fleck is shown a yellow card.72:05
Free kick awarded for an unfair challenge on Mark Noble by John Fleck.71:50
Stephen Crainey sends in a cross.71:01
Kevin Phillips sends in a cross, save by Henri Lansbury.69:34
Ricardo Vaz Te produces a right-footed shot from just outside the penalty box that misses to the left of the target.67:47
The offside flag is raised against Roman Bednar. Winston Reid takes the direct free kick.66:19
The referee blows for offside against Ian Evatt. Henri Lansbury takes the indirect free kick.64:37
Free kick taken by Matthew Gilks.64:37 Substitution
Substitution (West Ham) makes a substitution, with Gary O'Neil coming on for Abdoulaye Faye.64:37
Free kick awarded for a foul by Ricardo Vaz Te on Alex Baptiste.63:11
John Fleck takes a shot. Blocked by James Tomkins. Corner taken by Matt Phillips, clearance made by James Tomkins.62:53
The ball is crossed by Kevin Phillips, Joey O'Brien makes a clearance.61:18
The ball is swung over by Nicky Maynard, Alex Baptiste manages to make a clearance. Inswinging corner taken right-footed by Mark Noble from the left by-line, clearance made by Ian Evatt.59:41
Long range effort from Matt Phillips misses to the left of the target.58:43
Matt Phillips takes a shot. Blocked by James Tomkins.57:56
Stephen Crainey produces a strike on goal direct from the free kick, George McCartney gets a block in.57:56 Booking
Booking Booking for Winston Reid.57:20
The referee gives a free kick against Winston Reid for handball.52:29
Kevin Phillips fires a strike on goal direct from the free kick.52:29 Substitution
Substitution Henri Lansbury replaces Julien Faubert.52:29 Dismissal
Dismissal Robert Green is shown a red card for professional foul.52:20
Robert Green challenges Roman Bednar unfairly and gives away a free kick.51:37
George McCartney delivers the ball, clearance made by Craig Cathcart.50:32
Abdoulaye Faye challenges Kevin Phillips unfairly and gives away a free kick. Stephen Crainey takes the direct free kick.46:56
The assistant referee flags for offside against Ricardo Vaz Te. Indirect free kick taken by Craig Cathcart.46:20
Roman Bednar sends in a cross, John Fleck has shot on goal from just outside the penalty box which goes wide of the right-hand upright.45:01
The referee gets the second half underway.45:01 Substitution
Substitution (Blackpool) makes a substitution, with Roman Bednar coming on for Lomana Tresor LuaLua.45:01 Substitution
Substitution Nouha Dicko is brought on as a substitute for Ludovic Sylvestre.45:00 +2:06 Half time
Half Time The first half comes to an end.45:00 +0:45
Assist by Alex Baptiste.45:00 +0:45 Goal scored
Goal! - Kevin Phillips - Blackpool 1 - 2 West Ham Kevin Phillips finds the back of the net with a headed goal from close in. Blackpool 1-2 West Ham.45:00 +0:41
Alex Baptiste crosses the ball,45:00
Julien Faubert crosses the ball, clearance made by Ian Evatt.43:39
Shot from a long way out by Jack Collison goes wide of the left-hand post.41:40
The ball is swung over by Julien Faubert.37:17
Mark Noble crosses the ball.33:50 Substitution
Substitution Kevin Phillips joins the action as a substitute, replacing Chris Basham.32:54
The ball is sent over by Ian Evatt, Joey O'Brien manages to make a clearance. Inswinging corner taken right-footed by Ludovic Sylvestre from the left by-line to the near post, Joey O'Brien manages to make a clearance.31:26
Assist by Jack Collison.31:26 Goal scored
Goal! - Nicky Maynard - Blackpool 0 - 2 West Ham Nicky Maynard gets on the score sheet with a goal from inside the six-yard box low into the middle of the goal. Blackpool 0-2 West Ham.31:22
A cross is delivered by Jack Collison,27:08
Assist by Mark Noble.27:08 Goal scored
Goal! - James Tomkins - Blackpool 0 - 1 West Ham James Tomkins grabs a headed goal from close range. Blackpool 0-1 West Ham.26:36
Ian Evatt gives away a free kick for an unfair challenge on Nicky Maynard. The ball is delivered by Mark Noble,25:28
Centre by George McCartney.24:28
The ball is sent over by George McCartney, Effort on goal by Julien Faubert from inside the area goes harmlessly over the bar.22:13
Lomana Tresor LuaLua is flagged offside by the assistant referee. Robert Green takes the free kick.19:21
Lomana Tresor LuaLua has an effort at goal from just inside the box that misses to the left of the target.16:26
The assistant referee signals for offside against Jack Collison. Matthew Gilks takes the free kick.13:54
James Tomkins has an effort at goal from outside the area which goes wide left of the target.10:01
Free kick awarded for a foul by Joey O'Brien on Lomana Tresor LuaLua. Free kick crossed left-footed by Stephen Crainey from left wing, clearance made by Winston Reid.7:12
The offside flag is raised against Chris Basham. Indirect free kick taken by Robert Green.5:57
Nicky Maynard takes a shot. Craig Cathcart gets a block in. Inswinging corner taken by Mark Noble, Abdoulaye Faye has a headed effort from close range and clears the crossbar.5:28
The referee blows for offside against Julien Faubert. Matthew Gilks takes the free kick.3:34
Ian Evatt concedes a free kick for a foul on Nicky Maynard. Direct effort from the free kick comes in from Ricardo Vaz Te, save made by Matthew Gilks.1:31
Lomana Tresor LuaLua fouled by Winston Reid, the ref awards a free kick. Lomana Tresor LuaLua takes the free kick. Matt Phillips takes a shot. Save made by Robert Green.0:45
Julien Faubert crosses the ball, Ricardo Vaz Te has a header from inside the six-yard box and clears the crossbar.0:00
The match gets underway.
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