Reading returned to the English Premier League after securing automatic promotion with a 1-0 win at home to Nottingham Forest on Tuesday.
Mikele Leigertwood volleyed in an Ian Harte free-kick nine minutes from time for the only goal of the game at the Madejski Stadium.
Forest, though, came close to snatching an equaliser in stoppage time but substitute Marcus Tudgay's header was cleared off the line by Alex Pearce with the striker's follow-up kept out by Australian goalkeeper Adam Federici.
Victory took the Royals, who've won 46 points from a possible 51 since January, back to the top flight for the first time since 2008, with the players swamped by joyful Reading fans who swarmed onto the pitch at the final whistle.
With only the top two sides guaranteed promotion, victory gave Championship leaders Reading an unbeatable eight point lead over third-placed West Ham, with only a maximum of six on offer to the Hammers from their final two regular season league games.
Meanwhile second-placed Southampton took a giant stride towards promotion with a 3-1 win away to Peterborough, the visitors 2-0 up inside 10 minutes.
Jos Hooiveld headed the Saints into a fifth minute lead before, five minutes later, Billy Sharp doubled their advantage.
Sharp scored his second and Southampton's third in the 57th minute before Peterborough's Tommy Rowe pulled one back four minutes from time.
That left Saints on the brink of promotion as they now have a five-point lead over West Ham.
The Hammers remained third with a 1-1 draw away to strugglers Bristol City.
James Tomkins headed the Londoners into a 25th minute lead only for City to equalise four minutes later through Cole Skuse.
Had Bristol City won, they would have relegated both Portsmouth and Coventry.
Instead Portsmouth, Southampton's bitter south coast rivals, gave themselves hope of avoiding the drop, at least for the time being, with a 2-1 win at home to Crystal Palace.
Scott Allan fired Pompey, into a 32nd minute lead and, 10 minutes after half-time, Greg Halford made it 2-0 for Michael Appleton's men, who'd relegated bottom of the table Doncaster with a dramatic 4-3 win last weekend.
However, Palace ensured a nervous finale at Fratton Park when Darren Ambrose pulled a goal back for the south London side with a 71st minute penalty.
Pompey, docked 10 points for entering administration, knew a draw with Palace would relegate them to the third tier of English football for the first time in 29 years.
Ambrose twice went close to an equaliser and Palace's Paddy McCarthy had the ball in the back of the net only for his 'goal' to be ruled out for a foul on Portsmouth goalkeeper Jamie Ashdown.
But Pompey, five points from safety, hung on for a victory that preserved their Championship status.
Australian defender Shane Lowry's 66th minute header saw Millwall win 1-0 away to Coventry after visiting keeper Maik Taylor saved Gary McSheffrey's penalty.
Coventry, behind Portsmouth on goal difference, are now, like Pompey, five points from safety with two matches to play.
Blackpool and Cardiff all but made sure of playoff spots with 1-0 and 2-0 wins over Leeds and Derby respectively.
Meanwhile Hull beat Barnsley 3-1, Brighton drew 2-2 with Watford, Ipswich and Birminghan shared the points in a 1-1 draw.
Elsewhere, the matches between Leicester and Burnley and Middlesbrough and Doncaster both ended in goalless stalemates.