Chris Wood’s 23rd goal of the season and a Robert Green penalty save earned Leeds victory over promotion rivals Sheffield Wednesday at Elland Road.
Leeds climbed to fourth above Reading, who play Brighton at 17:30 GMT.
Wood, given lots of space as Wednesday appealed unsuccessfully for offside, poked in from inside the penalty area.
Owls striker Jordan Rhodes had a chance to equalise after Souleymane Doukara fouled Sam Hutchinson, but Green pushed his spot-kick onto the post.
Wednesday remain sixth, six points above seventh-placed Fulham, who face in-form Cardiff at 15:00 GMT.
A game of few chances was settled by a simple finish by Wood, who has found the net in 21 separate competitive games for Leeds this season.
And it is still possible that the New Zealand striker could score league goals against all 23 Championship clubs during 2016-17, having already netted against 16 different opponents so far this term.
Meanwhile, visiting forward Rhodes has scored only once in six appearances since his loan move from Middlesbrough in January.