Oldham piled on early pressure with former Blackpool midfielder Richie Wellens their main creative force.
A swirling gale ruined many of the attempts to play good football but, in the 28th minute, a sweeping move out of defence saw Andy Morrell slip a delightful pass into the path of Keith Southern and he crashed a 20-yard drive past Alan Blayney.
Once again Oldham tried hard to unlock the home defence at the start of the second half, but the Blackpool back four was marshalled superbly by Ian Evatt although his side had a lucky escape when Andy Liddell's effort was ruled controversially offside in the 56th minute.
The travelling support got something to cheer about with seven minutes left when substitute Matt Wolfenden scored with an effort that went in off the underside of the bar.
But Oldham's lingering hopes of a comeback were destroyed in stoppage time when Keigan Parker made up for some earlier misses with an 18-yard curler into the top corner.