Posh certainly deserved a reward for their efforts to even get the game on, club owner Barry Fry splashing out £4,000 to hire hot air blowers to thaw out heavily frost affected areas of the pitch.
The surface was hardly perfect and after solitary Country striker Liam Dickinson turned out to bring a good early stop from Mark Tyler, returning in goal after a five-match injury absence, the ball bobbled badly at the other end to deny Adam Newton a chance. David Farrell also failed to hit the target despite getting away from marker Rob Clare and taking the ball wide of County goalkeeper Jamie Spencer.
The game came to life after the break and Spencer kept his side in the hunt with fine saves from Paul Carden and defender Sean St.Ledger before County manager Jim Gannon tried to change the pattern of play with a double sub that almost came off.
Newcomers Ross Greenwood and Adam Le Fondre both quickly had Tyler in action, the keeper racing from his line to halt Le Fondre's break, but Posh's confidence grew with a greater share of the possession and the breakthrough came with a goal that was simplicity itself, Gain crossing to the far post where Holden claimed his first of the season steering a header wide of Spencer.
County tried to claw their way back to save an unbeaten away run under Gannon's leadership but Posh made sure of having the last word with Semple making the points safe firing past helpless Spencer following a determined 88th run.