Although Wigan were second best for much of a scrappy contest, they claimed a much-needed three points thanks to a close-range effort from debutant defender Jason Pearce in the 17th minute.
Wigan started the evening second from bottom and nine points from safety. They had not won in eight matches and only once in 14 games since Malkay Mackay replaced Uwe Rosler as manager in November.
Steve Clarke on the other hand had steadied the Reading ship since taking over from Nigel Adkins as manager in December. He had also steered them into the last eight of the FA Cup, in which they meet League One Bradford City.
It was therefore unsurprising that Reading made the brighter start at the Madejski Stadium, with Garath McCleary forcing a fine save from Wigan goalkeeper Ali Al-Habsi from his angled drive.
Reading captain Alex Pearce then nodded on Oliver Norwood’s corner only for Mark-Antoine Fortune to hack the ball off the goal line.
But Reading quickly lost their way, and Wigan went ahead in the 17th minute – mainly due to a double error from home keeper Adam Federici.
First, Federici dawdled on Alex Pearce’s backpass and, after being challenged by Leon Clarke, was fortunate to concede only a corner.
From the set-piece, Federici then fumbled Clarke’s downward header into the air.
After a scramble in the Reading area, Wigan centre-back Jason Pearce – on his debut on loan from Leeds United – bundled the ball home.
The hosts were stung into action but were unable to peg back the deficit before half-time.
Al-Habsi had to be alert, though, and made smart saves to keep out goal-bound efforts from McCleary and Nathaniel Chalobah.
Wigan sat back in the early stages of the second half, content with their lead, and allowed Reading to push forward.
Twice from Norwood corners, Reading should have done better.
First, Chalobah nodded wide when finding space at the far post, then Hal Robson-Kanu did similarly with another header.
Wigan responded with a scuffed shot from James Perch and a long-range attempt from substitute Kim Bo-kyung that flew over Federici’s crossbar.
But Mackay’s team mostly retreated deeper and deeper as they desperately clung on to the three points.
Reading tried everything they knew to break down the well-marshalled Wigan defence but grew desperate as the clock ran down.
Al-Habsi made a good save to keep out a fierce Norwood free-kick and home substitute Nick Blackman was denied by a superb last-ditch tackle from Perch.
Wigan could have snatched some breathing space near the end after James McClean’s piercing solo run.
But after Jordan Obita had almost deflected McClean’s cross into his own net, Pearce saved the day with a goal-line clearance. Wigan even survived 11 minutes of stoppage time to secure victory.