Martyn Waghorn scored a hat-trick as Derby came from behind to claim victory.
Match photographer David Lowndes captured some of the fans in the stands in this gallery.
Take a look and see if you can spot a familiar face.
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1. Posh 2 Derby 4
Peterborough United fans watch their side's defeat to Derby County. Photo: David Lowndes
2. Posh 2 Derby 4
Peterborough United fans watch their side's defeat to Derby County. Photo: David Lowndes
3. Posh 2 Derby 4
Peterborough United fans watch their side's defeat to Derby County. Photo: David Lowndes
4. Posh 2 Derby 4
Peterborough United fans watch their side's defeat to Derby County. Photo: David Lowndes
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