Oxford picked up their first league win since August by beating AFC Wimbledon.
Jake Forster-Caskey curled in a free-kick from 25 yards to put the hosts ahead, but Byron Harrison levelled with a close-range scissor-kick.
And Jim Fenlon's low drive from 30 yards put the managerless visitors ahead before the break, only for Deane Smalley to equalise from close in.
Yado Mambo hit the bar for the second time, and Alfie Potter compounded his misery by firing in the winner.
Chris Wilder's side had lost their last six League Two matches before Tuesday's game.
Oxford United manager Chris Wilder told BBC Radio Oxford:
"It was a big night for us and we had to turn up.
"It was a performance of determination and grit from everybody, the players and the supporters.
"For five, 10, 15 minutes after they scored their second it was a surreal atmosphere because our supporters gave the players a terrific boost to help claw ourselves back into the game.
"That gave us a platform at half time to go and win the game. I can only appreciate that support they gave us. We had young kids playing last night and they battled away and we deserved a touch of fortune.
"It wasn't a fantastic performance but it was a committed performance and one of real grit and heart."