On the quarter-hour mark, Emmerson Boyce had a chance for Wigan following a near-post run, but he subsequently fired over.
Eventually, Wigan were able to break the deadlock with just ten minutes to go in the first half, Riera drilling a low effort past Joe Lewis inside a crowded penalty area to claim his maiden goal for the club.
The away side would continue to live dangerously right until the end of the half, with Donervon Daniels blocking the ball on the line to deny McManaman with four minutes to go until the interval.
Blackpool were somewhat invigorated going into the second half. Nathan Delfouneso marauded into the Latics box, cutting inside on his right foot and sending a shot high and wide in the 52nd minute.
The former Aston Villa player threatened again just after the hour, but his first-time attempt was off target.
The game petered out towards the final stages, although there was drama in injury time when Blackpool claimed that a Wigan player had handled the ball in the area.
The referee, however, waved away the appeals, and the game duly finished with the home side claiming all three points.