The Posh development side were beaten 1-0 by Ilkeston Town on Wednesday afternoon.
Defender Jack Baldwin continued his comeback from a long-term knee injury as the Peterborough United development side were narrowly beaten by an Ilkeston Town side managed by former Posh coach Gavin Strachan.
The Ilkeston side included a number of former Posh graduates including Charlie Coulson, Ollie Luton, Joe Burgess and Liam Marshall, with the latter's late penalty the difference between the two sides.
Posh created a host of presentable chances with Deon Moore twice denied by the goalkeeper, while Jermaine Anderson also went close.
Conor Washington saw a well struck shot parried after good initial work to wriggle himself into the box, while Baldwin headed wide following a corner kick. Dion Henry made two decent stops at the other end, but could do little to stop the penalty.
Jonathan Edwards 45 minutes for Ilkeston and 30 minutes for Posh. He is currently on-loan with the non-league side.
Posh: Henry, Adebayo-Rowling, Davey (sub Humphrey), Baldwin (sub Maslen-Jones), Fox, Sadlier, Da Silva Lopes, J. Anderson, H. Anderson, Moore, Washington (sub Edwards).