Blackpool squandered a one-goal lead to lose at fellow relegation strugglers Oldham to leave them just five points ahead of the League One dropzone.
The Seasiders had found themselves 1-0 up at the half-time interval thanks to Kyle Vassell’s clever finish.
But the home side, who were in the bottom four before start of play, fought back to level it on the hour mark through Jack Byrne.
Oldham then dealt Blackpool the ultimate blow when on-loan Preston North End man Eoin Doyle won it with just five minutes to go.
It leaves Blackpool in 16th, five points ahead of MK Dons who occupy the last relegation place.
Gary Bowyer sprung something of a surprise with his team selection, making four changes from the side that played so poorly in the 2-1 defeat at home to Doncaster Rovers on Good Friday.
He ditched the 3-5-2 system that proved so ineffective against Doncaster, reverting back to the 4-2-3-1 formation.
It saw on-loan Middlesbrough midfielder Callum Cooke come into the side to make his first start since the 2-2 draw at home to Walsall on February 10.
Kyle Vassell also returned to lead the line for the Seasiders, having missed Friday's defeat with a slight knock.
Viv Solomon-Otabor and Danny Philliskirk also came into the starting eleven.
The four to make way were Will Aimson, Sean Longstaff, Armand Gnanduillet and Nathan Delfouneso - the latter left out of the squad altogether.
The presence of Mark Cullen on the substitutes bench will have provided a huge boost for the Seasiders ahead of their final run-in.
The striker has missed the majority of the season through a hamstring injury, with his last game coming in the 3-3 draw at Doncaster back in August.
Oldham made a bright start to the game and in the sixth minute, they were gifted an early opportunity to take the lead.
Rob Hunt swung in a low cross that Clark Robertson should have easily cleared, but the defender fluffed his lines allowing Eoin Doyle the chance to shoot at goal from close-range, but his tame effort was easily collected by Joe Lumley.
The hosts were keen to press Blackpool high up the pitch and that’s exactly what happened as Ousmane Fane robbed Jay Spearing of the ball before shooting wide of goal when he had options either side of him.
Blackpool’s first chance came on 12 minutes, when Jimmy Ryan curled just wide with a free kick from 25 yards out.
It was a real open start to the game and Oldham should have taken the lead on 15 minutes, when Lumley palmed a curling effort from Duckens Nazon into the path of Doyle, but the on-loan PNE man failed to convert from just a few yards out.
The Seasiders raced up the other end of the pitch and went close through Kyle Vassell, whose low effort was well saved by Johny Placide.
Doyle wasted yet another chance to give the home side the lead at the halfway point of the first half, but this time he didn’t know much about it.
Wilfied Moimbe provided a low cross from the left which hit the striker and looped over the crossbar after Curtis Tilt had failed to clear at the front post.
After the hectic start, the game soon calmed down with both sides settling into a rhythm and pressing from the front.
With 10 minutes to go until half time, Blackpool took the lead through Vassell who netted his 10th goal of the season.
The striker got across his man at the near post to get on the end of Colin Daniel’s cross, which he managed to deftly divert across the goalkeeper and into the far corner.
That proved to be the last action of the opening period, as Oldham struggled to find a reaction to Blackpool’s opener.
Saying that, the Latics almost found themselves level just two minutes into the second period but Doyle missed yet another gilt-edged chance.
Patrick McEleney’s cross in from the right-hand side evaded Clark Robertson and reached Doyle in space, but the striker headed over from close range.
The home side enjoyed all of the possession in the opening exchanges of the second half but Blackpool stood firm.
The Seasiders looked dangerous on the counter and they came close through Vassell once again, as the striker unleashed a powerful shot from range that Placide saved well.
But the home side’s pressure eventually told as they levelled on the hour mark through substitute Jack Byrne, who had only come off the bench moments earlier.
It came after Blackpool had failed to clear their lines from a corner allowing Byrne the chance to curl home from the edge of the box, giving Lumley no chance.
Jimmy Ryan was presented with a good opportunity to shoot at goal with a free kick on the corner of the Oldham box, but the Pool skipper opted to cross and the home defence managed to clear.
Byrne went close again for the home side, as he looked the pick out the bottom corner from the edge of the box only to shoot just wide.
Doyle had been extremely wasteful in front of goal but even he couldn't miss as he was presented with a free header just six yards out from goal.
The striker made no mistake, heading home to give the hosts the lead with just five minutes remaining.
Blackpool had opportunities to create chances in the dying stages of the match but their final ball and decision making was consistently found wanting, as Oldham held on for a win that took them out of the bottom four and left the Seasiders looking over their shoulders.
Oldham: Placide, Moimbe, Gardner, Edmundson, McEleney (Amadi-Holloway), Pringle (Bryne, Hunt, Fane, Bryan, Nazon (Obadeyi), Doyle
Subs not used: De La Paz, Wilson, Nepomuceno, Benteke
Blackpool: Lumley, Turton, Tilt, Robertson, Daniel, Ryan, Spearing, Cooke (Longstaff), Philliskirk, Solomon-Otabor, Vassell (Gnanduillet)
Subs not used: Mafoumbi, Aimson, D'Almeida, Menga, Cullen
Referee: Darren Drysdale
Attendance: 4,309 (616 Blackpool)