Guillem Bauza struck twice to give Swansea a 2-1 win over Gillingham which ensured the South Wales outfit will claim one of two automatic-promotion places in Coca-Cola League One.
Dennis Oli had given the relegation-threatened Gills a 22nd-minute lead when he finished well from inside the penalty area.
But Roberto Martinez' side equalised a minute before half-time when goalkeeper Derek Stillie failed to hold Andy Robinson's low shot and Bauza tucked away the rebound.
Stillie fumbled another Robinson shot moments later and Bauza took full advantage to fire in from the edge of the area.
Dougie Freedman (50, 69) scored a goal either side of Jonathan Howson's 59th-minute strike to give play-off chasing Leeds a 3-2 win over second-placed Carlisle at Elland Road.
Scott Dobie (17) and Danny Graham (60) both found the net for the Cumbrians, who are now three points clear of third-placed Doncaster.
Walsall are four points behind Gary McAllister's side after they recorded a 2-1 away win over struggling Cheltenham.
Tommy Mooney converted a 27th-minute penalty and Anthony Gerrard added a second a minute later for the Saddlers, while Paul Connor (74) pulled one back for the Robins.
Nathan Tyson (34) and Wes Morgan (51) were both on target for Nottingham Forest, who ran out 2-0 winners over Tranmere at Prenton Park.
Ian Westlake (51) and Glenn Murray (59) helped Brighton come back from Sam Parkin's (49) opener for Luton to claim a 2-1 win which kept Albion's play-off hopes alive and confirmed the Hatters' relegation.
Second-bottom Port Vale were also relegated after they were held to a 0-0 draw by Huddersfield at Vale Park.
Lee Barnard's 51st-minute equaliser cancelled out Colin Larkin's (24) opening goal as Southend consolidated their place in the play-offs with a 1-1 draw against Northampton.
Oldham's faint hopes of making the play-offs were boosted by a 2-0 win over Leyton Orient thanks to Chris Taylor (22) and Mark Allott (42), both of whom were on target at Boundary Park.
Goals from Darren Anderton (18) and Jo Kuffour (55) boosted Bournemouth's hopes of beating the drop as they clinched a 2-1 win over Bristol Rovers, who pulled a goal back through Ricky Lambert in the 56th minute.
A brace from Nicky Maynard (8, 58) and an injury-time strike from Tom Pope gave Crewe a valuable 3-0 win over Yeovil which enabled them to move three points above the relegation zone.
Millwall also moved a step closer to safety with a 1-0 away win over Hartlepool thanks to Jay Simpson's 11th-minute winner.