Peterborough's Dean Keates struck in stoppage time to cancel out Simon Cox's brace for Swindon.
Swindon denied victory in stoppage time
Swindon's Simon Cox looked set to spoil Peterborough's promotion party with a two-goal burst before Dean Keates saved their blushes with a stoppage-time equaliser.
With Posh sure of a move into the Championship and Swindon secure in League One, it could all have been irrelevant but Cox turned the form book upside down sweeping Swindon in front from 12 yards after 17 minutes.
After collecting no fewer than four player-of-the-season awards pre-match, Charlie Lee twice went close for the hosts early on, bringing saves from Swindon keeper Phil Smith before Craig Mackail-Smith levelled six minutes before the break with his 25th goal of the season.
But Posh were on terms for only three minutes before Michael Timlin set up Cox who side-stepped Craig Morgan's challenge before burying a shot past home keeper Joe Lewis for his 32nd of the campaign.
Aaron McLean failed from the penalty spot for Posh after 61 minutes, Smith saving at full stretch after sub Kevin Amankwaah brought down George Boyd, but Keates swept home a 30-yard free-kick in stoppage time.
