New striker Matt Godden was the man to head home in the 59th second. New midfielder Mark O’Hara also scored with his head on 27 minutes and Posh defended with few alarms until Rovers defender Tom Lockyer netted in the 93rd minute. Luckily there were only 60 seconds to play, although Posh had to survive a couple of further crosses before celebrating three points.
A slow start with a club record nine Football League debutants was a concern before the game, but that was dispelled in the first minute when Godden opened the scoring with a fine header.
Right-back Jason Naismith supplied the cross and pleasingly Posh had three players in the area waiting for the chance to score. That wasn’t often the case last season.
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And another cross on 27 minutes led to a second goal as O’Hara scored with a terrific header from left-back Colin Daniel’s centre.
Posh played with a 4-4-2 formation with Siriki Dembele, who exchanged neat passes with Daniel for the second goal, showing some good touches on one wing, but Rovers often outnumbered Posh in central areas and put some decent passing moves together without threatening new goalkeeper Aaron Chapman.
Former Posh striker Tom Nichols scooted clear early on, but found no power in his shot, while Ed Upson shaved a post with a 20-yard strike.
Rovers won the shot count in the first half 9-5.
And the visitors came out sharp at the start of the second-half with Posh centre-back Ryan Tafazolli making a terrific last-ditch tackle to thwart Liam Sercombe.
But a game played in sweltering heat died on its feet thereafter as Posh sat back content to keep a weak strike force at bay.
There were hardly any worrying moments until injury time when two decent stops from Chapman looked like preserving a clean sheet until Lockyer stooped to head home.
Posh: Aaron Chapman, Jason Naismith, Colin Daniel, Ryan Tafazolli, Rhys Bennett, Alex Woodyard, Mark O’Hara, Siriki Dembele (sub Louis Reed, 81 mins), Joe Ward, Jason Cummings (sub Callum Cooke, 61 mins), Matt Godden (sub Mathew Stevens, 87 mins). Unused substitutes: Conor O’Malley, Josh Yorwerth, George Cooper, Tyler Denton.
Rovers: Sam Slocombe, Daniel Leadbitter (sub Gavin Reilly, 61 mins), Tom Lockyer, Tony Craig, Ed Upson, Liam Sercombe, Chris Lines, James Clarke, Kyle Bennett (sub Sam Matthews, 67 mins), Alex Rodman, Tom Nichols (sub Bernard Mensah, 70 mins). Unused substitutes: Adam Smith,Tom Broadbent, Michael Kelly, Luke Russe.
Goals: Posh - Godden (1 min), O’Hara (27 mins).
Rovers - Lockyer (90 + 3 mins).
Cautions: Posh - O’Hara (foul).
Rovers - Bennett (dissent), Nichols (foul).
Referee: John Busby 5.
Attendance: 6,439 (803 Rovers).
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