The Whites are now looking at being dragged into a relegation fight after being made to pay for poor efforts at either end of the field to hand Malky Mackay his first win as Wigan manager.
Leeds boss Neil Redfearn made two changes from the side that had some encouragement with a draw at Nottingham Forest, bringing Guiseppe Bellusci back in defence in place of Jason Pearce and more surprisingly leaving out Adryan in favour of Michael Tonge.
But one of the players Redfearn has put his faith in made an error to give United the start they dreaded as centre-back Liam Cooper chested the ball into his own net after attempting to cut out James McClean’s cross.
Leeds looked to hit back with Stephen Warnock getting forward to smash a half-volley over while Chris McCann headed over for Wigan from a corner.
United had their best chance on 28 minutes when Billy Sharp met Mirco Antenucci’s cross with a header that looped over keeper Scott Carson only to hit the crossbar.
It stayed 1-0 to half-time, although Tommaso Bianchi curled one effort wide from the edge of the box, Antenucci’s shot was easily saved and Sharp hit another shot wide.
At the other end, Marco Silvestri saved with his legs to deny Marc-Antoine Fortune.
Redfearn made two changes for the start of the second half, bringing on the fit-again Rodolph Austin and striker Steve Morison with Alex Mowatt and Bianchi going off and a change in formation needed.
Rob Kiernan hit a shot wide for Wigan before Leeds mounted some good pressure with Antenucci having an effort deflected wide following a good run by Lewis Cook and Bellusci denied by former United keeper Carson from close range.
Carson made more saves from Cook and Austin while Wigan occasionally threatened and Silvestri saved from McClean with Bellusci clearing the ball to safety.
It turned into one of those days for Leeds in front of goal as Morison saw his header tipped over by Carson and Sam Byram and Austin wasted opportunities.
Inevitably, maybe, it was Wigan who scored seven minutes from time when McClean got in behind the home defence and lashed a shot past Silvestri to ensure the points would be going back over the Pennines.
Defeat was maybe hard on Leeds, but head coach Neil Redfearn offered no excuses and said his team were not clinical enough up front and were paying for an inability to keep a clean sheet.
Leeds United 0
Wigan Athletic 2
(Cooper og 11, McClean 83)
Friday, December 26, 2014
Sky Bet Championship
Leeds: Silvestri, Byram, Bellusci, Cooper, Warnock, Tonge, Bianchi (Morison 45), Mowatt (Austin 45), Cook, Antenucci, Sharp (Doukara 70).
Wigan: Carson, Tavernier, Taylor, Ramis, McCann, Watson, McClean, Cowie, Perch, Kiernan, Fortune (Espinoza 70).
Referee: Nigel Miller.