Second-half goals from George Boyd and former Old Trafford youngster Nicky Ajose were enough to clinch victory for Posh even if another tough work-out will benefit many of the players likely to either be involved at Under-21 level next term or head out on loan for league action.
Sam Johnstone had to be alert to repel Grant McCann's near-post free-kick early on but the Reds started to gel with captain Davide Petrucci often looking to link up with lone striker Federico Macheda. Nick Powell's ambitious shot wide was the first real effort of note from Warren Joyce's side but, cheered on by a noisy away following, the football started to flow with Larnell Cole displaying some sublime touches.
Yet Posh came closest to scoring on the half-hour mark when Lee Tomlin's clever disguised pass allowed Joe Newell to fire just wide. Substitute keeper Joe Day, on for Robert Olejnik, saw Jesse Lingard's right-foot shot ripple the side-netting before the hosts finished the half marginally stronger. Grant McCann had a couple of attempts, a dipping drive into Johnstone's arms and a speculative volley off target, while Tom Thorpe made an excellent sliding block to divert Jonson Clarke-Harris' shot behind for a corner.
A much-changed Peterborough line-up came out of the blocks quickly after the restart with Tomlin forcing a spectacular tip-over from Johnstone. The keeper then fed Lingard with an excellent pass and the winger burst forward to set up Macheda, but the Italian's finish from a tight angle failed to trouble Day.
The deadlock was broken on 56 minutes when Michele Fornasier's stray pass out of defence put the Reds on the back foot and Boyd lashed a