American striker Dom Dwyer popped up with a 90th-minute winner for Mansfield with his first touch of the ball as struggling Rotherham were beaten 2-1.
Jordan Hugill gave the visitors an early lead from the spot but second-half goals from Tyler Roberts and Dwyer consigned the Millers to a third successive defeat.
The Stags were furious when handball was given in the seventh minute as Frazer Blake-Tracy blocked a close-range Hugill shot.
Hugill sent Liam Roberts the wrong way from the spot to open the scoring.
Mansfield’s Will Evans had two shots blocked almost on the line in the 31st minute before Rhys Oates appealed unsuccessfully for a penalty after going down in the box.
Rotherham came close to a second after 36 minutes as Josh Benson’s free-kick rattled the crossbar.
But the Stags equalised in the 62nd minute when a quick throw-in from Oates sent Roberts into space on the left and he beat Cameron Dawson with a superb low finish.
Dwyer then had the final say, heading in an Aaron Lewis free-kick from close range a minute after joining the action.
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