But not all kick on to have particularly good careers which is a warning to those who were handed surpise opportunities in the Championship last season.
Here are the 20 youngest Posh players to represent the club at second tier level in the Football League. The list includes five who made their Championship debut last season.
1. 20th RYAN BENNETT
Debut v Barnsley (home) October 31, 2009 aged 19 years and 239 days. Posh signed this teenage centre-back from Grimsby for £500k and he became one of the club's greatest defenders, starring in the League One promotion season of 2010-11. Bennett made exactly 100 Posh appearances before joining Norwich City for around £3million. He played for the Canaries in the Premier League and also played for Wolves and Leicester before moving to Swansea City in October 2020, where he remains. Photo: georgi mabee
2. 19th HARRISON BURROWS
Championship debut v Derby County, August 14, 2021 aged 19 years, 214 days. Burrows had made 25 Football League appearances for Posh before he made his second tier debut for the club in the first home game of last season. He scored in a 2-1 win and went onto enjoy a fine season with the promise of much more to come. Photo: Joe Dent
3. 18th BEN AMOS
Championship debut, October 31, 2009 v Barnsley aged 19 years and 204 days. Posh had a goalkeeping crisis which forced manager Darren Ferguson to raid his old club Manchester United for an emergency loan signing. Amos made his debut for Posh in the same game as Ryan Bennett, a 2-1 defeat at home to Barnsley, when the 'keeper didn't exactly cover himself in glory. Amos never played for Posh again, but went on to have a decent career at Charlton and Bolton among others and last season he was a regular in the Wigan Athletic side that won League One. Photo: Joe Dent
4. 17th DANNY ANDREW
Championship debut v Blackpool, April 24, 2010 aged 19 years and 122 days. This youth graduate was given two appearances towards the end of a Championship relegation season and was released soon after. The left-back fought his way back into the Football League though and played well for Macclesfield, Fleetwood, Grimsby and Doncaster before re-joining Fleetwood Town. Now 31 he could well be back on Posh's radar after over 300 senior appearances in total. Photo: Joe Dent