Leeds United leapfrogged Sheffield United into second place in the Championship after a 2-0 win away at Preston North End on Tuesday.
Patrick Bamford scored twice as Marcelo Bielsa's side moved two points ahead of the Blades, who are in action against Birmingham City on Wednesday.
West Brom's automatic promotion hopes suffered a potentially fatal blow with a 3-2 defeat to Bristol City, while Middlesbrough boosted their play-off hopes with a win away at struggling Bolton Wanderers.
There were also wins for Blackburn Rovers, Sheffield Wednesday and Swansea City against Derby County, Nottingham Forest and Stoke City respectively.
BAMFORD PUNISHES 10-MAN NORTH END
Leeds and Sheffield United are locked in a pulsating battle for the Championship's second automatic promotion place and Bielsa's side have cranked up the pressure ahead of the Blades' visit to Birmingham.
Their cause was helped by the dismissal of Ben Pearson, who received a straight red card for hauling down Bamford as he went through on goal shortly after the interval.
The visitors took full advantage of their numerical superiority in the 62nd minute when Bamford powered home from 25 yards.
The former Chelsea striker then added a second 14 minutes from time, heading in Mateusz Klich's right-wing cross to seal a vital three points.
BAGGIES' TOP-TWO HOPES DEALT A BLOW
West Brom are now nine points behind Leeds in fourth after three goals in the opening 19 minutes set Bristol City on their way to a important victory in the play-off battle.
The Robins, who are four points ahead of seventh-place Middlesbrough in fifth, stormed ahead thanks to goals from Josh Brownhill, Andreas Weimann and Jack Hunt.
Dwight Gayle reduced the deficit two minutes into the second half before Jay Rodriguez added a second 16 minutes from time.
They were unable to find a leveller, though, as caretaker boss Jimmy Shan suffered a second defeat in four days.
FLETCHER KEEPS PULIS' MEN IN PLAY-OFF RACE
Middlesbrough ended a torrid run of form to push Bolton Wanderers closer to relegation.
Tony Pulis' side had lost their last six games in the league, but Ashley Fletcher scored twice to move them to within two points of sixth-placed Aston Villa.
Bolton, meanwhile, remain eight points from safety with just five games left to preserve their Championship status for another season.
RAMS WELL BEATEN IN LANCASHIRE
Derby County's hopes of sneaking a play-off place suffered a setback as Blackburn Rovers ran out 2-0 winners at Ewood Park, while Sheffield Wednesday jumped above Nottingham Forest into ninth after a resounding 3-0 win at Hillsborough.
Elsewhere, Swansea City ran out 3-1 winners over Stoke City at the Liberty Stadium.