They also saw a very rare EFL record equalled when Shrewsbury Town striker John Marquis was sent off just 13 seconds into the game, equalling the fastest red card from the start of a game in English professional football.
Chris Conn-Clarke scored his first Peterborough goal in the win on a good day for the hosts.
Here are just some of the Posh fans who saw the drama unfold, captured through the lens of David Lowndes. Take a look and see who you know.
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1. Posh 3 Shrewsbury 1
Peterborough United eased their relegation fears with a 3-1 win over Shrewsbury Town. Photo: David Lowndes
2. Posh 3 Shrewsbury 1
Peterborough United eased their relegation fears with a 3-1 win over Shrewsbury Town. Photo: David Lowndes
3. Posh 3 Shrewsbury 1
Peterborough United eased their relegation fears with a 3-1 win over Shrewsbury Town. Photo: David Lowndes
4. Posh 3 Shrewsbury 1
Peterborough United eased their relegation fears with a 3-1 win over Shrewsbury Town. Photo: David Lowndes