Jamie Allen gave the Brewers an early lead but a thrilling game burst into life with three goals in the final ten minutes as Liam Boyce and Marcus Harness scored either side of a Cauley Woodrow penalty to seal a precious victory.
Allen was on the spot in just the fifth minute to prod home his eighth goal of the season after Burton’s fast start was rewarded when Scott Fraser’s low shot was spilled by Barnsley keeper Adam Davies giving the Burton midfielder a simple finish.
Boyce’s missed a glorious chance just two minutes into the second half when he was guilty of only finding the waiting hands of Davies after trying to dink him when straight through on goal.
Harness was also close to a second for Albion with a shot that beat Davies and trickled past the post on 67 minutes giving Barnsley the encouragement to push for an equaliser.
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But Boyce had a second chance one on one with Davies on 81 minutes and this time he didn’t miss drilling home from just outside the box.
Woodrow halved the deficit from the penalty spot on 85 minutes after Jake Buxton had been penalised for a high boot but Harness secured the points for Burton with a minute of normal time remaining when Boyce found him unmarked in the centre.
No record equalling twenty-one game unbeaten run then for the Tykes who on the day lacked their usual defensive solidity as a big three points eluded them.
Barnsley: Davies, Pinnock, Lindsay, Hedges, McGeehan, Woodrow, Cavare, Pinillos (Adeboyejo 84), Thiam (Bahre 59), Mowatt, Brown (Styles 59).
Subs: Walton, Jackson, J Williams, B Williams.
Burton: Collins, Brayford, Buxton, Allen (Wallace 90), McFadzean, Fraser (Fox 78), Akins, Harness, Quinn, Daniel, Boyce (Miller 90).
Subs: Bywater, Bradley, Hutchinson, Clarke.
Referee: Michael Salisbury