A goal of the season contender from Reds midfielder Joe Williams lit up a Halloween night clash as the visitors ran out 4-2 winners at the Pirelli Stadium.
Reds boss Paul Heckingbottom rang the changes from Saturday's 1-1 draw with Sheffield Wednesday. Zeki Fryers, Brad Potts, Ike Ugbo and Lloyd Isgrove all came into the starting eleven, Jason McCarthy, Adam Hammill, Mamadou Thiam and Tom Bradshaw dropped out, with McCarthy missing from the matchday squad altogether due to injury.
It was a slow start to the game on a rather chilly evening in Staffordshire, with the Reds, as usual, cheered on by a healthy travelling contingent.
The first moment of quality came in the 21st minute when Isgrove, starting his first game for Barnsley since the playoff final win at Wembley against Millwall last May, burst into the Burton box, played a quick one-two with Harvey Barnes and lashed the ball past Connor Ripley into the top corner.
It really was a game bereft of clear cut chances, Andy Yiadom blocked a fierce Lucas Akins shot, while at the other end Cameron McGeehan fired high over the bar after good work from Yiadom.
But the Reds invited Burton pressure and it told on 37 minutes as a whipped cross from the right by Jake Buxton was headed in at the back post by Matty Lund.
Maybe that's what they needed, because just three minutes later the Reds were back in front. Ugbo did well to battle past two Burton defenders before advancing on goal. He had support but decided to go for goal, his shot was parried by Ripley but Brad Potts followed up to fire home the rebound.
Brewers defender Kyle McFadzean received medical attention for a knock in the build-up to Potts' goal and in the four minutes that were added for that, the home side equalised once again. Scannell cleverly found Lloyd Dyer in a pocket of space and the tricky winger darted into the box and smashed in low to Davies' left.
Half Time - Burton Albion 2-2 Barnsley.
The home side came out for the second half with their tails up and were by far the better side for the opening fifteen minutes. McFadzean had a header saved by Davies.
Now, I've seen Heckingbottom criticised for some of his changes so far this season. But the two he made on 67 minutes absolutely changed this game for me. Ike Ugbo was replaced by Tom Bradshaw and George Moncur replaced McGeehan.
73 minutes. It is rather difficult to describe what happened next. Yiadom lifted a lovely ball to Isgrove, he crossed into the box and it was headed away as far as Joe Williams. Fully 30 yards out, Williams took the ball on his chest and hit a stunning, dipping volley off the underside of the bar and in. One of the best goals you'll ever see.
The Reds had Adam Davies to thank for preventing a third Burton equaliser, as they pushed forward in search of a fourth goal, the home side countered and Akins fed Scannell, who took a touch which allowed Davies to rush from his goal to block the winger's effort. A really top save.
The game was over on 87 minutes as the Reds clinched a fourth. Isgrove found Moncur, who stormed into the box, went past two before seeing his shot saved by Ripley and cleared.
But it came straight back and Moncur played the ball to Harvey Barnes on the left, he cut inside, beat two and fired the ball beyond Ripley to seal all three points and send the rowdy away end into raptures.
It could even have been five, if the referee had agreed with the Reds players and fans and given a penalty for what looked like a definite foul on Bradshaw. But it didn't matter as the final whistle blew and gave the Reds their second away win of the season.
Full Time - Burton Albion 2-4 Barnsley
Adam Davies - Made two good saves, particularly the one from Scannell in an otherwise quiet evening for the Reds stopper. 7
Andy Yiadom - Got forward well and showed some cracking bits of skill. Still looks a bit rusty but fitness will come with more game time. 7
Liam Lindsay - Solid if unspectacular. Rarely beaten in the air. 6
Angus MacDonald - Probably allowed Dyer through too easily for their second, but some colossal headers in the last ten. 6
Zeki Fryers - Made some good interceptions and looked assured on the ball. Another one catching up with his fitness. 6
Joe Williams - Usual busy self, everywhere in midfield and an utterly unbelievable strike to put the Reds 3-2 up. 8
Cameron McGeehan - Decent display in the engine room. Got stuck in and went close first half. 6
Brad Potts - Seems the criticism he got from some early on in the season has spurred him on. Powerful display, capped off with a goal. 7
Lloyd Isgrove - Great to see Izzy back in red. Tireless performance, a constant thorn in Burton's side and a fine goal. 9
Harvey Barnes - Didn't see too much of him really until he burst into the box in the 87th minute to smash in the Reds' fourth. 6
Ike Ugbo - For me, too lightweight and not willing to graft hard enough. Did well to get into a position to shoot which led to Potts' goal. Can't start ahead of Bradshaw. 6
Tom Bradshaw (for Ugbo, 67) - Won more in the air in 23 minutes than Ugbo did in 67. Gave the Reds fresh impetus. 7
George Moncur (for McGeehan, 67) - Provided a bit of flair in the Reds midfield and was instrumental in the fourth goal. 7
Unused Subs: Walton, Pearson, Bird, Hedges, Hammill, Thiam.
Reds Man of the Match: Lloyd Isgrove
Burton Man of the Match: Jake Buxton.
Referee: Jeremy Simpson - Picky and inconsistent. 4