Andy Dorman struck late to secure victory for Bristol Rovers and dent Rotherham's play-off hopes.
Both teams struggled to create chances in the first half with the Millers' Alex Revell firing over the bar.
Lewis Grabban should have put the home side ahead but shot wide after collecting Revell's first-time ball over the top.
Dorman snatched victory for the visitors in added time with his low shot from inside the area.
Rotherham United manager Andy Scott tells BBC Radio Sheffield:
"If you don't do enough to win the game then you always leave yourself open to losing it.
"Smash and grab whatever you want to call it, but they came for a point and got three. I don't think we really deserved to win the game, but neither did they.
"It was a poor game, especially in the first half, both sides cancelled the other out and there was never really any danger of a goal going in.
"Second half we came out with more intent and showed what we were about but we're leaving it until the second half to do that and lose a goal right at the end."
Bristol Rovers manager Mark McGhee told BBC Radio Bristol:
"The referee joked with me that it was a bit of a Dick Turpin result, but I didn't think it was quite like that.
"In the second half we didn't keep the ball half as well as we did first half and we didn't cause them the sort of problems that we did in the first half.
"We missed chances in the first half, in the second half we didn't. So from that point of view they had the majority of play in the second half, but it was all stuff from distance into the box. I didn't feel too worried that they were going to score.
"We defended well, had a good shape and we saw it through so I don't see it as a smash-and-grab."