Barnsley failed to create enough clear cut chances to trouble Premier League Palace but, more importantly, Simeon Jackson and Ryan Williams got some much-needed game-time under their belts.
With the Reds hoping to end their losing streak, they began an uphill struggle as they conceded with barely 25 seconds on the watch.
Despite Barnsley having kick-off themselves, Palace stormed forward with Keshi Anderson racing onto a chipped pass and slotting beyond Walton, who did get a touch but the shot was too powerful.
Anderson was making a nuisance of himself and did get a shot away after a decent run on 19 minutes but his shot was straight at Walton.
Jackson got in behind on 21 minutes after a brilliantly weighted pass for the striker was played in by Williams, but the Canadian international's angle was narrowing and he couldn't get a meaningful shot away.
The visitors came close to making it 2-0 twice in the space of two minutes just before the break. First Anderson was inches away from sweeping Diamond's cross in from three yards before Diamond himself absolutely lashed a shot at goal from 20 yards only for his thunderous effort to hammer the bar.
As the first half drew to a close, Simeon Jackson found the ball at his feet 12 yards out and hit a decent effort on the turn. Gregory did well to hold the striker's effort.
After a sluggish opening, it was a carbon copy start to the second half as Palace found the net early on again. A chipped ball into the box found Gray and he tucked beyond Walton from eight yards.
Barnsley responded with Maris spraying a pass out wide for Bree, the defender's delivery was excellent as Harry White connected with a header but it lacked direction and drifted wide on 49 minutes.
It was 3-0 on 50 minutes as the Reds were once again caught out by a ball over the top. Keshi Anderson registered his second of the afternoon with a cool finish into the far corner.
Harry White blasted over in what was a decent chance for the Reds to pull one back, whilst at the other end Jack Walton made two excellent saves to keep the score down.
Anderson had his hat-trick in the bag on 76 minutes when a shot cannoned back off the post and along the line, allowing the striker one of the easiest of goals of his career to make it triple delight for himself and four for Palace.
The Reds kept plugging away and George Maris got on the end of a good move but couldn't steer his effort low enough from 20 yards as the clock ticked down. Moments later, Chippendale cracked at goal forcing Gregory to punch clear.
Reds: Walton, Bree, Templeton, Digby, Scott, Drennan, Kneeshaw, Maris, White, Jackson, Williams (Chippendale 61)
Subs not used: Cowgill, Murphy, Gooda, Alton.
Crystal Palace: Gregory, Wynter, Fryers (Allasani 76), Hoare (Breimyr 66), McCarthy (Forte 76), Croll, Bissaka, Diamond, Anderson, Gray.
Subs not used: Perntreou, Akiotu.