Jack Payne sealed the points for Colchester with a late penalty against his former club before Callum Hendry was sent off in stoppage time.
It leaves the Dons in a lowly 17th place as the season continues to fizzle out.
Our photographer Jane Russell captured these pictures of some of the fans who saw the game unfold. Take a look and see who you know.
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9. Dons 0 Colchester 1
Jack Payne came back to haunt MK Dons to give Colchester victory at Stadium MK. Photo: Jane Russell
10. Dons 0 Colchester 1
Jack Payne came back to haunt MK Dons to give Colchester victory at Stadium MK. Photo: Jane Russell
11. Dons 0 Colchester 1
Jack Payne came back to haunt MK Dons to give Colchester victory at Stadium MK. Photo: Jane Russell
12. Dons 0 Colchester 1
Jack Payne came back to haunt MK Dons to give Colchester victory at Stadium MK. Photo: Jane Russell