Hessey took a quick set piece as Conrad Logan set up his wall before the referees whistle to leave the Millers flat footed.
In truth though Stanley deserved a share of the spoils despite Rotherham having much the better of the first half on a very windy and rainy evening in Lancashire.
The Millers played some decent stuff despite the conditions and were rewarded before the break as skipper Ryan Cresswell headed home Danny Schofield's corner.
With the wind with them after the restart Gareth Evans was denied with a right foot shot with alot of problems for the home side coming through the dangerous Marcus Marshall, as Lewis Grabban amd Dale Tonge also went close.
But Hessey nicked a share of the points when his free-kick went in off the post.
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