Alan Lee's close-range goal earned the 10 men of Crystal Palace a 1-1 draw at London Road and ensured Peterborough's slow return to the Coca-Cola Championship continued.
Shaun Batt put Darren Ferguson's side ahead early in the second half at the end of the first decent move of the game before Lee bundled in a leveller.
Palace defender Paddy McCarthy was sent off with 16 minutes remaining for a second booking but the visitors survived to emerge with a point.
McCarthy was booked in the first half for a cynical foul on Craig Mackail-Smith and fouled the same player at least five times before being shown a second yellow card.
Ferguson's side remain without a win in the league this season but were the better side throughout a poor game.
Palace had put in a spirited display in a Carling Cup defeat to Manchester City last Thursday but lacked any form of guile or drive until they fell behind.
Palace goalkeeper Julian Speroni twice did well to claim crosses from the left as the home side started at a high tempo but the game soon descended into a scrappy affair.
Neil Danns volleyed over and Mackail-Smith fired in a low shot as a dour first half drew to a close.
The game was severely lacking in quality but the home side forged ahead in the 53rd minute through Batt.
George Boyd span away from Danny Butterfield on the left and clipped a pass with the outside of his left foot to Batt on the right wing.
He surged past Clint Hill and planted a powerful effort across Speroni from just inside the area.
It was a fine finish from the former Fisher Athletic winger but he was guilty of squandering an equally good chance just two minutes later.
Again Boyd was the architect as Posh broke away from a Palace corner and his precise pass played Batt into a similar position.
This time Batt chose to try and pass to Mackail-Smith but saw his ball easily cut out by the recovering McCarthy.
Palace suddenly looked interested and equalised with a scrappy goal in the 64th minute.
A Darren Ambrose corner was not dealt with, and when McCarthy sent a header back across the six-yard box Lee was able to prod the ball over the line from two yards out.
Posh substitute Tommy Rowe then carved open the defence with a positive run, but Mackail-Smith was unable to locate a team-mate with the cross from the left.
McCarthy was then dismissed for a second booking as referee Kevin Friend lost patience with his game-long duel with Mackail-Smith.
Palace manager Neil Warnock was unsurprisingly unhappy with the decision but his side reorganised well and saw out the remainder of the game relatively untroubled.
Teams:
Peterborough Lewis, Martin, Morgan, Zakuani,Williams (Lee 85), Batt (Rowe 70), Frecklington,Diagouraga (Coutts 66), Boyd, Mackail-Smith, Mclean.
Subs Not Used: McKeown, Keates, Pearce, Green.
Booked: Boyd, Frecklington.
Goals: Batt 53.
Crystal Palace Speroni, Butterfield, McCarthy, Fonte, Hill,Ambrose (Ryan Smith 69), Derry, Danns, N'Diaye (Moses 69),Sears, Lee.
Subs Not Used: Flahavan, Clyne, Carle, Scannell, Lawrence.
Sent Off: McCarthy (74).
Booked: McCarthy.
Goals: Lee 64.
Att: 8,473
Ref: Kevin Friend (Leicestershire).