Neil Warnock's first home game in charge of Leeds United ended in defeat as Championship leaders Southampton rode their luck on the way to a 1-0 victory.
A 16th minute goal from Rickie Lambert gave the south coast club the lead, but the result owed just as much to the heroics of Southampton goalkeeper Kelvin Davis. A string of world-class saves kept Warnock's side at bay before Saints survived a late scramble in the box which saw Luciano Becchio and Darren O'Dea hit the crossbar within seconds of each other.
However, Southampton's four point lead at the top of the table was short lived after the Hammers cut their lead to one point following a 2-0 win over Carling Cup runners-up Cardiff.
A tidy finish just before half-time from West Ham captain Kevin Nolan gave his side the lead before George McCartney sealed the win in the second half, sending the Hammers within touching distance of a return to the Championship summit.
In-form Reading maintained the pressure on the top two after a late strike from Adam Le Fondre stole three points from struggling Millwall. Andrew Keogh had given the Lions an unlikely first half lead but they were quickly pegged back by a classy Hal Robson-Kanu volley.
Millwall were then cruelly undone with 15 minutes remaining as a Le Fondre tap-in gave the Royals their sixth straight Championship victory.
The rest of the playoff-chasing pack had a mixed weekend with both Birmingham and Blackpool having to make do with home draws. An injury-time equaliser from Matty Fryatt cancelled out a fine Thomas Ince goal in the North-West while Derby fought back from two down to earn a point at St Andrews.
However, Brighton's 1-1 draw at bottom of the table Doncaster meant Chris Hughton's side held onto sixth spot and the crucial last play-off place.
Elsewhere, Middlesbrough piled even more misery onto Portsmouth, leaving Michael Appleton's Pompey languishing in 23rd after a 3-1 defeat, while Boro climbed back into the play-off places.
Ipswich and Leicester also continued their fine recent form with comfortable home wins over Bristol City and Coventry respectively.
Steve Cotterill's resurgent Nottingham Forest followed up last weekend's surprise victory over Birmingham with a hard-earned draw over Barnsley while Mile Jedinak's first goal for Crystal Palace gave the Eagles a one-nil win over Peterborough.
Finally, Watford answered Sean Dyche's call for a positive response to last week's 3-0 home loss to Southampton by taking all three points from play-off chasing Burnley. Eddie Howe's side had taken a 2-0 lead before three goals in a 20-minute second half spell sent Hornet's fans home happy.