The gulf in class was there for all to see at Oakwell as stylish Swansea, hailed the best footballing side in the Championship in many quarters, tore their relegation-haunted hosts apart with some silky football.
They enjoyed a dream start with a goal after just two minutes. Barnsley conceded a needless free-kick just outside the box and the game's outstanding player, Jordi Gomez, swung in a delightful set-piece that was stabbed home from six yards by centre-back Ashley Williams.
It was just what the visitors required to settle them down but it was disastrous for Barnsley, who knew they needed points to keep them out of the bottom three.
From that point on Swansea were in cruise control and only a smart double save from Barnsley's German keeper Heinz Muller prevented Swansea from extending their advantage on the half-hour mark.
Muller firstly saved superbly from Mark Gower and then managed to scramble across his goal to deflect a Gomez shot behind for a corner.
But Swansea did manage to go two-up nine minutes before half-time. Gomez was allowed too much time and space 25 yards out and the Spaniard produced a cracking left-foot drive that flew through the legs of Barnsley captain Stephen Foster and beyond Muller's flailing left hand.
Barnsley huffed and puffed but, despite the excellent efforts of winger Adam Hammill, on-loan from Liverpool, the home side looked bereft of attacking options and Swansea put the issue beyond doubt in the 67th minute following a defensive howler.
Gomez was again involved in the build-up but his hopeful looking cross looked meat and drink for Barnsley keeper Muller.
However, the giant German, having caught the ball, collided with Foster to leave Jason Scotland with the simplest of tasks in rolling the ball into an unguarded net.
The outstanding Gomez was then only denied a fourth goal by Muller's brave block.
Barnsley did manage a consolation goal six minutes from time after being awarded a fortunate penalty for an alleged handball. Malta international Daniel Bogdanovic coolly converted his fourth goal for the club from the spot.