Two goals from midfielder Mark O’Hara (he now has three in two League One games) and strikes from front two Jason Cummings and Matt Godden enabled Posh to come from behind to make it six points from two matches.
Posh left new striker Ivan Toney on the substitutes’ bench and alongside him was 41 year-old goalkeeping coach Mark Tyler. Tyler’s presence ahead of Conor O’Malley was to fulfil a Football League directive involving having one ‘home developed’ player in a matchday squad.
But the absence of a £600k striker was rendered irrelevant in a first-half that yielded three Posh goals, after they had fallen behind to a dodgy penalty decision.
Colin Daniel appeared to pull out of tackling home right-back Joe Rafferty in the 17th minute, but the home full-back threw himself to the ground anyway while persuading referee Anthony Backhouse contact had indeed been made. Ian Henderson sent Posh ‘keeper Aaron Chapman the wrong way from the spot.
But Posh responded well. Gifted young winger Siriki Dembele had already seen one swerving shot saved from 30 yards when he crossed from the left enabling Cummings to head home from close range on 26 minutes.
And eight minutes later a Dembele free kick was headed back across goal by Cummings for O’Hara to claim his second goal in two matches.
And Dembele made it a hat-trick of assists on the stroke of half-time when he shot straight at goal from a free-kick despite an acute angle. The ball might have travelled across the line before home ‘keeper Josh Lillis reached it and parried the ball away from goal, but Godden was on hand to convert the rebound.
Dale, who played some fine passing football, should have equalised moments earlier when some pinball in the Posh area ended with the ball at Matt Done’s feet at the far post, but he scuffed badly wide from close range.
Dale changed their patient passing approach soon into the second period by sending on a second big striker in Calvin Andrew to partner Aaron Wilbraham.
Wilbraham was soon heading over from a Brad Inman cross before Matt Godden was denied a second goal for Posh by a terrific Lillis save.
Dembele then struck the top of the crossbar on the hour mark as Posh continued to threaten on the break.
Dale did enjoy lots of possession while chasing the game, but rarely looked like scoring until Aaron Chapman made a fine save from an Andrew header 10 minutes from time. Ntlhe knocked the rebound over the bar.
And Posh put some gloss on the final scoreline deep into added time when Toney and O’Hara combined to rob a dithering Dale player on halfway. O’Hara strode clear to score with ease.
Posh: Aaron Chapman, Jason Naismith, Colin Daniel, Rhys Bennett, Ryan Tafazolli, Alex Woodyard, Mark O’Hara, Siriki Dembele (sub Callum Cooke, 85 mins), Joe Ward, Matt Godden (sub Josh Yorwerth, 90 + 2 mins), Jason Cummings (sub Ivan Toney, 72 mins). Unused substitutes: Mark Tyler, Louis Reed, Tyler Denton, George Cooper.
Rochdale: Josh Lillis, Joe Rafferty (sub Calvin Andrew, 50 mins), Ryan Delaney, Harrison McGahey (sub Andy Cannon, 66 mins), MJ Williams, Callum Camps, Matty Done (sub Kgoisi Ntlhe, 77 mins), David Perkins, Aaron Wilbraham, Bradden Inman, Ian Henderson.
Unused substitutes: Jimmy McNulty, Ollie Rathbone, Brendan Moore, Daniel Adshead,
Goals: Posh - Cummings (26 mins), O’Hara (33 mins & 90 + 4 mins), Godden (45 + 3 mins).
Rochdale - Henderson (pen, 17 mins).
Cautions: Posh - Woodyard (foul)
Dale - McGahey (foul).
Referee: Anthony Backhouse (Cumbria) 6.
Attendance: 3,693 (565 Posh).
Alan Swann was at the match for the Peterborough Telegraph so check back for match reaction.
Also follow @PTAlanSwann on Twitter for live match updates.