Kgosi Ntlhe was sent off as Posh conceded a late equaliser as Barnsley earned a point at Oakwell.
An equaliser deep into stoppage time earned Barnsley a point from their clash with Peterborough United at Oakwell as Conor Washington's first half strike was cancelled out right at the death.Alan Sheehan curled a free-kick into the wall in the early exchanges as Posh took advantage of some rather comical defending by the hosts to win the set-piece.
The deadlock was broken on 17 minutes as Jack Cowgill was punished for a clear air kick and Conor WASHINGTON made him pay, firing home past goalkeeper Davies with style.
Moments later and another error allowed Harry Anderson to nip in but his shot was saved by Davies. Zakuani did well to block a fierce effort from Lalkovic on 26 minutes as the Tykes responded well to the early jitters.
Hourihane fired with his left-foot after a mistake by Smith as Barnsley came close to the leveller on 34 minutes.
Posh had a massive let off on 39 minutes as a long ball forward was misjudged by Alnwick, who completely missed his header and allowed Hourihane the opportunity to slide the ball into an empty net, but he contrived to fire wide.
One minute of added time was indicated, but there was nothing to report during that period.
Hourihane curled wide of the target after Lalkovic sprung the Posh offside trap on 51 minutes. Sam Winnall headed into the side-netting moments later as Alnwick misjudged a flighted Hourihane cross.
Anderson squandered a fine chance to double the lead on 69 minutes after some excellent wing play from Maddison but he fired wide as the ball landed at his feet on the half volley.
Posh introduced Erhun Oztumer for Maddison on 77 minutes as Dave Robertson made his first substitution.
Posh were reduced to 10-men on 78 minutes as Ntlhe was shown a second yellow card for a foul by the touchline.
Four minutes of added time was indicated by the fourth official and during that period, youngster Jonny Edwards replaced Washington.
Deep into stoppage time, the home side found an equaliser as a corner swung into the near post was met by former Cambridge man Luke BERRY to secure a point for the Tykes.
Full-time: Barnsley 1-1 Peterborough United
Barnsley: Davies, Holgate, Cowhill (sub Bree 65min), Nyatanga, Smith (sub John 56min), Hourihane, Digby (sub Pearson 57min), Berry, Lalkovic, Winnall, Scowen. Unused sub: Dibble, Oates, Williams, Cranie.
Posh: Alnwick, Ntlhe, Smith, Zakuani, Santos, Maddison (sub Oztumer 77min), Beautyman, Anderson, Sheehan, Washington (sub Edwards 90min), Bostwick. Unused subs: Henry, Brisley, Norris, Burgess, Newell.
Attendance: 8,924 (380 Posh).