Midfielder Nicky Wroe scored twice to give the Reserves their first win since October.
Reserves result: Barnsley 2 Preston 1
Wroe got in behind the Lilywhites defence on 36 minutes to score his first before Preston snatched an equaliser in stoppage time through Jeff Smith.
Two minutes from time Wroe scored his second to give the Reds a deserved win.
Brian O'Callaghan's comeback from injury lasted just 24 minutes before he limped off.
Brian O'Callaghan's comeback from injury lasted just 24 minutes before he limped off.
BARNSLEY team: Alcock, Harban, O’Callaghan (Laight 24), Tonge, Atkinson, Heslop, Wroe, Lumsdon, Baker, Jones, Jarman. Subs: Oldham, Flinders, Batley.