Andrew Crofts’s second-half strike inflicted a first home defeat of the season on Wigan, and claimed Albion a third successive win.
In an even contest, Oscar Garcia’s side showed their play-off credentials by coming away from yet another former Premier League home ground without conceding a goal.
In a lively opening it was the Latics who threatened first as Tomasz Kuszczak clawed away Chris McCann’s looping header, while up the other end Bruno’s drilled effort was beaten away by Lee Nicholls.
Fresh from his international debut, Gordon Greer was on hand to deny Nick Powell’s near-post effort before the 2013 FA Cup hero Ben Watson flashed wide.
Powell was proving the main threat for the hosts but once again Albion’s Polish keeper had the measure of the forward, comfortably collecting his low drive.
But after the flurry of early chances the game became tighter, with both sides finding that killer pass hard to come by.
However some intricate play in the middle created space for Powell once again, but the Manchester United loanee couldn’t find the target with his strike, and neither could Marc-Antoine Fortune just moments later.
Wigan had edged the first half but Albion almost snatched the lead straight after the break when Ashley Barnes’s cross was met by the unmarked Jake Forster-Caskey, who saw his header saved by Nicholls.
The hosts responded through Callum McManaman although once again Kuszczak was equal to the strike.
But the chance of the game landed at the feet of substitute Grant Holt, who after wrestling the ball off Greer, was one-on-one with Kuszczak but screwed his shot wide.
Within a minute, Albion capitalised. David’s cross from the right was powerfully headed at goal by Forster-Caskey, only for Nicholls to produce an absolutely spectacular save. However Crofts battled to the rebound first and his looping header dropped into the net.
Albion almost doubled their advantage just moments later through Craig Conway, though Nicholls wasn’t to be beaten as he produced another excellent save.
The final moments saw Owen Coyle’s side throwing all they had at the Seagulls goal, and once again Albion had their Polish keeper to thank as he pulled off a remarkable one handed save low to his left to deny Holt, and with that confirmed the points were on their way back to the south coast.