The Reds kicked off a crucial Easter weekend in the perfect fashion, edging out the Shrews at a red-hot Oakwell to maintain their position in the second automatic promotion spot in Sky Bet League One.
Goals in either half from Alex Mowatt and Jacob Brown helped the Reds to an enormously important victory as the race for the Championship enters the final furlong.
Head Coach, Daniel Stendel had named an unchanged starting XI for this one, with the most notable change being that of the inclusion of Kieffer Moore amongst his substitutes; the big striker back involved after two months out injured.
But it was the visitors who began the game the brightest, and after a mere three minutes Barnsley were indebted to their skipper for keeping the game goalless.
Tyrese Campbell played in Shaun Whalley for Shrewsbury, but Adam Davies came out fast to block the shot and the Reds escaped.
Stendel's men weren't showing enough in the final third but they did edge ahead on 23 minutes when Mowatt took it upon himself to try his luck and alter his sides' fortunes. With his right foot he bent home a superb effort from all of 25-yards giving away 'keeper Jonathan Mitchell no chance.
That spurred the visitors on and after Greg Docherty flashed an effort wide, on 37 minutes Campbell hit a ball sweet as a nut first time, and it flew in low and true beyond the strectching hand of Davies.
HALF TIME: Barnsley 1-1 Shrewsbury
Straight after the break and the visitors nearly went in front when former Barnsley academy player Luke Waterfall headed towards goal at the far post but it bounced off the ground and onto the roof of the net.
Two minutes later and another let-off as Campbell's volley flashed an inch or so wide well-placed.
Barnsley rallied and Cameron McGeehan rattled the crossbar with a rocket from just inside the area but then two minutes later, the renewed vigour paid off as a flowing Reds move culminated in a cracking finish by Brown at the near post.
The 64th minute saw the introduction of Moore, to an amazing ovation from three sides of Oakwell. He replaced Mike Bähre who'd set up Brown's goal.
Mowatt dribbled beyond a handful of defenders before curling an effort towards the top corner but a deflection saw it fall just wide of the post.
With just over 10 minutes remaining Davies produced an outstanding one-handed save to claw away a Scott Golbourne effort that look destined for the top corner. The ex-Red couldn't believe it didn't go in.
There were sub appearances for Ryan Hedges and Callum Styles and both were involved in the Reds retaining possession and seeing out the win for a huge three points.
FULL TIME: Barnsley 2-1 Shrewsbury
Davies, J.Williams, Pinnock, Jackson, Pinillos, Mowatt, McGeehan, Brown, Thiam (Hedges), Bähre (Moore), Woodrow (Styles).
Unused: Walton, Fryers, Green, Cavaré.