While the Posh are 22nd in the table with 15 points from 19 games, the Colliers are a position adrift in 23rd place, trailing them by four points.
The visitors have also appointed a new manager in Poya Asbaghi, who replaced Markus Schopp after he was given the boot following a run of seven consecutive defeats.
He won his first game in-charge, but it now seems like a false dawn, with Barnsley losing the next three.
Peterborough, too, are stuck in a rut and are now coming off the back of a stunning 4-0 loss to Blackburn Rovers.
Peterborough United vs Barnsley Head-To-Head
There have been 38 clashes between the sides before, with Peterborough narrowly edging Barnsley with 17 wins to 16, while only five of their encounters have ended in a draw.
However, each of their last three meetings have gone Barnsley's way, keeping a clean sheet in all of them.
Peterborough United Form Guide (all competitions): L-L-L-D-L
Barnsley Form Guide (all competitions): L-L-L-W-L
Peterborough United vs Barnsley Team News
Following a 4-0 rout at the hands of Blackburn Rovers on Thursday, it wouldn't be surprising to see head coach Darren Ferguson make a few changes to his XI.
Josh Knight was an unused substitute in the said game and could start on Saturday, while Harrison Burrows is also pushing for a starting berth.
Midfielder Joel Randall played for the under-23 team recently after a lengthy layoff from injury. This game might be too soon for him though.
Doubtful: Joel Randall
Despite a loss to Swansea in their last game, the Colliers frustrated their visitors for large spells with a solid defensive structure. It might convince new manager Poya Asbaghi to play four-at-the-back again.
However, it's their attack that needs fixing, with the side netting only 13 times in 19 games so far.
Peterborough United vs Barnsley Predicted XI
Peterborough United (3-4-1-2): David Cornell; Nathan Thompson, Mark Beevers, Josh Knight; Joe Ward, Jack Taylor, Oliver Norburn, Dan Butler; Siriki Dembélé; Sammie Szmodics, Jonson Clarke-Harris.
Barnsley (4-3-3): Brad Collins; Callum Brittain, Michał Helik, Jasper Moon, Jordan Williams; Callum Styles, Josh Benson, Romal Palmer; Dominik Frieser, Cauley Woodrow, Devante Cole.
Peterborough United vs Barnsley Prediction
It's a contest between two relegation battling sides who're on a torrid run of form right now and occupying two of the bottom three places in the table.
As much as they'd be eager to end their respective winless runs, it seems like a low-scoring draw would be the outcome.
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Prediction: Peterborough United 1-1 Barnsley