Newly-appointed Rotherham boss Steve Evans watched from the stands as the Millers recorded a third straight league victory against promotion hopefuls Cheltenham.
Evans, who departed Crawley after nearly five years in charge, was revealed as Andy Scott's replacement a few hours before kick-off and his new charges left it late as they maintained their late push for the play-offs, skipper Ryan Creswell heading home Ben Pringle's corner in the final minute of stoppage time.
Caretaker boss Darren Patterson - in charge for Saturday's game - said: "It was a really first-class header from Ryan that won it, and a first-class delivery from Ben Pringle. A very, very pleasing result for everybody.
"Ryan's a big lad and the last three games he has played he has been first class. The three points were fully merited today against a good side. We dominated the first half and we really took the game to them.
"I am delighted with the three points but if we had kept a few more clean sheets we would have been up there in the play-offs.
"Cheltenham showed what a good side they are, but we dominated possession and our goalkeeper had very little to do again. We didn't get frustrated, we kept believing and kept moving it and we kept going and that really pleases me."