Posh fielded a much-weakened side and were defeated 2-0 by a motivated Cheltenham side who kept themselves alive in League One with victory.
Posh are now set to finish fourth in the table unless they record an unlikely thumping of Bolton on the final day.
RATINGS KEY: 10-Out of this world, 9-Brilliant, 8-Excellent, 7-Very Good, 6-Okay, 5-Poor, 4-Stinker
1. NICHOLAS BILOKAPIC
Not a glorious return to the side. Spilled right into a dangerous area for the first goal, gave the ball away with this feet on several occasions, putting his team into trouble, and almost scored a comical own goal in the first half. Did make a couple of good saves to but the damage was already done. 4. Photo: Joe Dent
2. HARLEY MILLS
An impressive night. Did what he could in defence on a touch night and pushed forward well. Put some good deliveries into the the box and could have had an assist had Clarke-Harris buried a header late in the game. Also took the corners and did we well. 7. Photo: Joe Dent
3. ROMONEY CRICHLOW
All of Posh's problems came from their shaky backline. They were all over the place under pressure in the opening stages in both halves. Had no control over Matty Taylor. Found badly wanting for both goals with mistakes and inactivity. 4. Photo: Joe Dent
4. EMMANUEL FERNANDEZ
He is far too causal for his own good. Which gets him into trouble on the ball. Part of a wide open centre-back partnership that could have conceded far more than two. 4. Photo: Joe Dent