Centre-back and skipper Mark Beevers is the oldest at 31 with teenage defender Ronnie Edwards the youngest of three 18 year-olds. Aaron Powell and Ricky-Jade Jones are also 18.
Here are some facts about the men most likely to be entrusted with keeping Posh in the Championship...
21.
JOE WARD. Age: 25. App 146. Goals 15. FACTS: Wide player Joe has made more Posh appearances than any other member of the current squad having moved from non-league Woking in January, 2018. He scored his first Posh goal in a 2-2 draw at Sunderland later that year.
22.
JOEL RANDALL: Celtic, Norwich City and Charlton Athletic were among the clubs reportedly interested in signing midfielder Joel before he sensibly opted for Posh. He is the sixth million pound signing of the Darragh MacAnthony era after Tyrone Barnett, Britt Assombalonga, Mo Eisa, Sammie Szmodics and Jonson Clarke-Harris. Photo: Midlands