Leeds manager Marcelo Bielsa. AFP/Adrian DENNIS
Patrick Bamford gave Leeds an early lead at before second-half goals from substitute Ezgjan Alioski and Jack Harrison took them three points clear of West Brom.
Only the top two clubs at the end of the regular season are guaranteed promotion to the Premier League.
West Brom are still five points clear of third-placed Brentford despite a l-0 loss to the London club on Friday.
At Elland Road, a minute’s silence took place before kick-off in memory of former Leeds players Norman Hunter and Trevor Cherry, who both died in April.
There were no fans present, however, with spectators barred on health grounds in a bid to prevent the spread of the coronavirus.
Leeds took a 10th-minute lead when Bamford scored his 14th goal of the season after running on to Helder Costa’s cutback.
They doubled their lead against fellow promotion contenders Fulham in the 56th minute when Harrison raced on to Mateusz Klich’s pass down the right before his ball into the box was turned home by Alioski.
Harrison added a third goal and Fulham’s defeat was compounded when substitute Neeskens Kebano was sent off in stoppage time for his trip on Luke Ayling, a second bookable offence.
“In the first half, it was difficult for us to recover the ball in the opponent’s half and when we were close to our box we lost it again quickly,” Leeds head coach Marcelo Bielsa told BBC Radio.
“That is why the first half was better for them than for us. In the second half it was better.
“The win was necessary for us and very important.”
Preston dropped out of the play-off places after losing 3-1 at home to Cardiff, who swapped places with the Lilywhites and are on 60 points.
Below them, Derby climbed up to eighth and boosted their play-off hopes by beating Reading at Pride Park 2-1 with former Manchester United and England striker Wayne Rooney on target for the Rams.
At the other end of the table, veteran boss Neil Warnock won his first match as Middlesbrough manager with a 2-0 victory away to fellow strugglers Stoke.
Goals from Ashley Fletcher and substitute Marcus Tavernier took Boro two points clear of the relegation zone.
Barnsley slipped to the bottom of the table after a goalless draw with Millwall.
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