Barnsley lost at home on Saturday to lowly Scunthorpe United managed by their former boss Mark Robins.
Marcello Trotta got his first Reds goal after 29 minutes but the Iron replied seconds later through Paddy Madden who then made it 2-1 in first half injury-time.
It was a poor performance from the Reds and, although they improved in the second half and had several good chances, they slipped to 15th in the table, eight points off the play-offs and three above the relegation zone.
Danny Wilson made one change from the team that lost at Chesterfield a week earlier with Kane Hemmings dropping to the bench and being replaced by Trotta.
Hemmings only had 22 minutes to wait to come onto the field after Barnsley's in-form striker Sam Winnall pulled up with an injury against his former club. Wilson confirmed later that it is a hamstring problem and the player is likely to miss at least the derby with Doncaster on Tuesday as will captain Martin Cranie who picked up his fifth booking of the season just after Winnall's injury.
Scunthorpe were the better side in the opening half an hour and almost took the lead when Lyle Taylor blazed over from just inside the box.
Taylor was shown how it is done a minute later by Trotta who smashed a left-footed shot into the top left corner from 12 yards after a good run and pass by left-back Joe Dudgeon.
The lead lasted less than a minute as Ross Turnbull could only parry Gary McSheffrey's shot to Paddy Madden who levelled.
Trotta almost put Barnsley back in front in spectacular fashion on 40 minutes when he controlled a waist-high Hemmings cross with his back to goal, turned 15 yards out and volleyed straight at visiting goalkeeper Sam Slocombe who saved with ease.
It was the visitors who scored next when Peter Ramage gave the ball away and Madden was allowed the run 30 past a despairing James Bailey and scuff a 15-yard shot past Turnbull into the bottom left corner.
Jean Yves M'voto, brought on for Ramage early in the second half, missed a glorious chance for 2-2 when he ran onto Conor Hourihane's right wing free-kick but sliced wide from five yards out at the back post.
There was then a fantastic opportunity for Devante Cole as he brilliantly brought down Dudgeon's pass and beat a defender but fired well over from 12 yards with the goal gaping.
Scunthorpe could have made it 3-1 against the run of play when Taylor went clean through after skipping around M'voto but the former Sheffield United man shot too close to Turnbull who saved well to keeper the Reds in the game.
Luke Berry and Trotta headed corners from substitute Keith Treacy well wide in the final minutes.
Team: Turnbull; Cranie, Ramage (M'voto 52mins), Nyatanga, Dudgeon; Bailey (Treacy 66), Hourihane, Berry, Trotta; Winnall (Hemmings 22), Cole.
