Blackpool were unable to hold onto their early lead as they succumbed to a narrow defeat at promotion-chasing Barnsley.
The Seasiders took the Tykes by surprise by breaking the deadlock early on, Harry Pritchard seeing his deflected effort wrongfoot the Barnsley keeper.
But the home side, roared on by an expectant home crowd, got back on level terms through Cauley Woodrow to make it 1-1 at the break.
Liam Lindsay was left unmarked from a corner to nod home what turned out to be the winner for Barnsley.
Blackpool were unable to issue much of a response in their penultimate game of the season and their last away trip of the campaign.
Barnsley were in command for large swathes of the game but wasted a number of opportunities to make the result more comfortable.
The Seasiders were boosted by the return of Jimmy Ryan to their match day squad for the first time in almost 12 months.
The midfielder, who was named among the substitutes, last featured for Pool on the final day of last season and has since been sidelined with a knee injury.
Terry McPhillips made two changes to his starting line-up, bringing Harry Pritchard and Antony Evans back into the fold.
Matty Virtue and Chris Long were the two players to drop out, Virtue missing from the squad altogether after suffering a gash to his leg in the Easter Monday win against Fleetwood Town.
Donervon Daniels wasn’t fit enough to return to the squad, remaining on the sidelines with Mark Howard, Ollie Turton and Max Clayton.
After a quiet opening, Blackpool were the first to threaten when their three-on-two move broke down after Marc Bola skipped past a couple of challenges, only for Armand Gnanduillet’s pass to go astray.
But Gnanduillet atoned a minute later, setting up Harry Pritchard with a smart flick-on, the ball falling nicely for the midfielder at the back post.
Pritchard took the shot first-time and it took a wicked deflection to wrongfoot Barnsley keeper Adam Davies, the ball settling into the bottom corner to hand the Seasiders an early lead.
Barnsley looked to hit back immediately, Mamadou Thiam squandering a priceless chance a couple of minutes later when he headed over the bar from inside the six-yard box after getting on the end of a right-wing cross.
Ben Heneghan was then called into action to make a vital last-ditch block to deny Mike Bahre’s goalbound effort.
Cameron McGeehan tried an ambitious effort from 25 yards for the home side but his impressive shot on the turn curled just wide of the far post.
Pool wasted a half-chance when Barnsley failed to clear their lines from a free kick, Michael Nottingham heading back into the box in the direction of Heneghan who could only loop a header of his own over the bar.
Christoffer Mafoumbi was quick off his line to make a save with his legs to deny Thiam, who had gone in behind Pool’s backline down the left.
There was nothing Mafoumbi could do to deny Barnsley levelling matters five minutes before the interval though.
Barnsley’s top scorer Cauley Woodrow was given too much time to turn on the edge of the Blackpool box and he took full advantage, unleashing a low shot beyond Mafoumbi.
The home side were straight onto the front foot at the start of the second half and had penalty appeals waved away when Alex Mowatt went sprawling inside the box.
Bahre then wasted another good opening for Barnsley, glancing a header over the bar from a corner.
The Seasiders were grateful to Mafoumbi eight minutes into the second period when he made an impressive save from Thiam, tipping over the winger’s effort which had looked destined for the top corner.
Barnsley’s relentless pressure eventually told on the hour mark as they got their noses in front for the first time.
It came via defender Liam Lindsay, who headed home from inside a crowded six-yard box from McGeehan’s corner.
The Seasiders were given two huge let-offs in the space of a minute when Woodrow failed to hit the target when left unmarked eight yards out from goal, before the forward lashed well over when well placed in front of goal.
Pool had struggle to create openings since going behind, but they were given a half chance of sorts when a corner was cleared to Pritchard on the edge of the box, only for the scorer of the Seasiders’ opener to see his stabbed effort well claimed by Davies.
Kieffer Moore missed an absolute sitter of a chance to make it 3-1 to Barnsley when he somehow managed to side foot over the bar from no more than four or five yards out from goal.
Barnsley, recognising the importance of holding onto the three points, began to look a little nervy in the dying stages and substitute Liam Feeney did go close to an unlikely late equaliser, striking the outside of the post from a tight angle.
That proved to be the last real action of the game as the home side held on for a vital win, with the full-time whistle seeing a number of Barnsley fans invade the pitch although automatic promotion has not yet been secured.
Barnsley: Davies, Pinnock, Lindsay, Bahre (Styles), Williams, Pinillos, Thiam (Hedges), Mowatt, Brown (Moore), McGeehan, Woodrow
Subs not used: Walton, Fryers, Green, Jackson
Blackpool: Mafoumbi, Nottingham, Heneghan, Tilt, Bola, Spearing, Pritchard (Long), Kirby (Delfouneso), Thompson, Evans (Feeney), Gnanduillet
Subs not used: Boney, Anderton, Ryan, Guy
Referee: John Busby