But the result maintained a six-month sequence which has seen Blackpool fail to pick up a home win since Easter and will do little to ease the pressure on boss Simon Grayson.
It all started so bravely for the home side who dominated the opening 45 minutes and kept former Seasider Les Pogliacomi busy in the Oldham goal.
The breakthrough finally came four minutes before half-time and in slightly bizarre fashion with former Oldham man Scott Vernon left to claim a strike he knew little about.
Good work down the flank by Simon Gillett and Keith Southern saw a good cross whipped into the area which Oldham defender Will Haining could only deflect off Vernon and into the net.
But the second half was a very different story with Richie Wellens in dominant form against his former club.
Wellens found the equaliser in controversial circumstances on 63 minutes with a rasping long-range shot which initially looked set to be ruled out as there was a Latics player in an offside position.
The referee overruled his linesman and awarded the goal to dismay of the home supporters.
Oldham took the lead nine minutes later when a cross from Paul Warne wasn't dealt with properly by the Blackpool defence and striker Chris Porter headed home from close range.
That should have been enough for Oldham but in the dying seconds Blackpool midfielder Claus Jorgensen dragged a cross to the far post where Morrell made no mistake.