You have to go back to the mid-1970s for the last time that the South Yorkshire neighbours were toiling together quite so badly in the lower divisions - almost neck-and-neck in the standings.
A chronic lack of goalscoring conviction - make that just plain old conviction at times - and some cheap concessions have pockmarked a pretty distressing landscape for Reds and Rovers followers.
Both clubs will be mindful of sticky FA Cup assignments against non-league opponents on the horizon too. Barnsley visit Altrincham, cup giant-killers of yore, next weekend and Rovers welcome Stalybridge. Failing to progress there would put the tin lid on proceedings, you’d venture.
Here are the problems for the flagging pair, in a nutshell.
Goalscoring - or lack of it
Rovers are the lowest scorers in League One with 11 goals, while Barnsley have mustered 15.
Aside from Sam Winnall, who has struck four times, the only other designated Reds forward to find the net is Conor Wilkinson, who struck once, with the Reds’ attacking potency further diminished by an injury to key man Conor Hourihane. Loan signing Michael Smith is yet to get off the mark for the Reds as well. It never rains, but pours.
On the road, Doncaster have scored just three times, the lowest tally in the Football League along with Charlton Athletic and Huddersfield Town, with Rovers big summer signing, Andy Williams, suffering from a crisis of confidence somewhat.
Nathan Tyson is only just back form injury, while Curtis Main has been sidelined all season, with much of the emphais on young rookie Keshi Anderson.
Darren Ferguson may have only been at Doncaster for a few weeks, but given his utterances, he probably feels he has spoken about Rovers defensive deficiencies far too much already. Try until he is blue in the face.
Lamentable goals were conceded in the back-to-back losses to Millwall and Peterborough, with Rovers having displayed a soft centre from set-plays all season. All successful sides are build on clean sheets and Doncaster’s last one arrived on August 19 - one of just two registered just seeason. For a side in the bottom four of League One, it is both a grim and worrying statistic.
There are similarities at Oakwell, with the Reds having also shipped some bad and crass goals on occasions this season - think concessions in grating home losses to Crewe and Shrewsbury in particular. Barnsley have also struggled on the clean sheet front - just three in the league so far.
A lack of confidence
Barnsley head coach Lee Johnson has alluded to this in recent weeks, with the issue being particularly pressing, given that the majority of his line-up are fresh-faced and relative newcomers in the game.
Johnson was a streetwise midfield operator in his playing days with a number of clubs and how Barnsley could do one or two of his ilk to navigate and plot a course around the pitch during the winter grind - with the Reds game management poor so far this season.
Rovers also look decidedly flat and down at heel if the evidence of much of this season is anything to go by. A lack of consistency in results means that confidence is fragile - a case in point being the late derby win over Barnsley, which was followed by an aimless JPT performance at York City.