West Ham clinched promotion to the Premier League as Ricardo Vaz Te's late winner sealed a dramatic 2-1 victory over Blackpool in the Championship play-off final at Wembley on Saturday.
Sam Allardyce's side survived a nervous start to take the lead through Carlton Cole's first half strike, but Tom Ince equalised soon after the break and Blackpool had several good chances to go ahead.
Portuguese forward Vaz Te made the Seasiders pay for their profligacy when he struck from close-range in the 87th minute to ensure the Hammers returned to the top-flight just 12 months after relegation.
Vaz Te's winner was crucial for a club who had invested heavily in winning promotion and the east London outfit's place in the Premier League will rake in between £45 million and £90 million in increased revenue according to varying reports.
"Blackpool were every bit as good as us but we just swung it in our favour. It's 49 games this season and it's the first time we've won a game in the last few minutes," Allardyce said.
"I'm just delighted to be back in the Premier League. It means everything to me because I had been in the Premier League for 10 years or so (before being sacked by Blackburn in 2010).
"It was difficult at the start to turn this club around but we have come good at the end."
Defeat was cruel on Blackpool, who almost made the perfect start when poor defending from Matt Taylor allowed Stephen Dobbie to squeeze past him and drive in a low strike that Robert Green pushed onto his near post.
That narrow escape seemed to unsettle West Ham and their defence parted with alarming ease as Matt Phillips surged clear, only to shoot tamely at Green with just the goalkeeper to beat.
West Ham's nerves were on show again when right-back Guy Demel made a hash of clearing on the edge of his own penalty area and Phillips stole possession before curling just wide with the goal at his mercy.
But West Ham, making their first appearance at Wembley since 1981, gradually grew into the match and, after Vaz Te fired just wide, Allardyce's team took the lead in the 35th minute.
As Blackpool appealed in vain for a foul on Ince, Taylor looked up and dinked a sublime diagonal pass over the Seasiders defence towards Cole, whose perfect first touch brought the ball under control before his second guided a cool strike past Matt Gilks.
West Ham finished third, 11 points ahead of fifth-placed Blackpool, but spent most of the season struggling to cope with the demands of their fans and directors, who had both expected automatic promotion.
And they looked like cracking again as Ince fashioned a fine equaliser early in the second half.
Ince's father Paul has never been forgiven for posing in a Manchester United shirt prior to moving to Old Trafford from West Ham and the young winger was taunted by the Hammers fans at Wembley.
They were silenced in the 48th minute when West Ham's defenders failed to deal with Phillips' long pass towards Ince, who produced a superb first-time strike angled across Green into the far corner.
Alex Baptiste should have given Ian Holloway's men the lead seconds later when he ran onto a Kevin Phillips pass, but the defender's prodded effort was cleared off the line by Taylor.
Blackpool threatened again as a flowing move cut through the Hammers defence to set up Dobbie, who clutched his head in frustration after scuffing woefully wide from Neal Eardley's cross.
But West Ham captain Kevin Nolan hit the bar with a ferocious volley in the closing stages.
And it was Nolan who proved the catalyst for West Ham's winner as he found the energy to sprint down the left before whipping over a low cross that caused havoc in the Blackpool defence.
Baptiste failed to clear and Cole flicked the ball towards Vaz Te, who had the simple task of firing high into the empty net from close-range to spark wild celebrations.