A Bertie Bradshaw try put the hosts up in the Yorkshire derby, before Lloyd Hayes landed a penalty for the leaders.
Bradshaw’s second, added to by Seramaia Turagabeci, was responded to by Andrew Foster and Hayes for 12-10 at the break.
A Hayes penalty and Callum Bustin try gave Rotherham the lead, but Nathan Greenwood’s seven-pointer midway through the final quarter proved decisive.
Albion and Club cut gap at top
Second-placed Plymouth Albion eased to a 35-10 victory at Clifton.
Iwan Jenkins converted early tries by Joe Bailey and Harrison Legg before Ollie Harris crossed for the hosts.
But Plymouth led 21-5 at the break thanks to a Shea Cornish score and Jenkins, and the bonus was confirmed a minute into the second period.
Jenkins landed again before Harris doubled up, but Albion sealed the deal as Frankie Dart added to Bailey’s second.
Blackheath are up to third after a thrilling 29-27 triumph at Bishop’s Stortford.
Matt Dalrymple converted a Jordan Burns effort to put Club in front, but they trailed 15-7 at half time after Tom Hitchcock and Isaac Bell crossed, Chris Bolton with five points from the tee.
Billy Harding continued his amazing record of scoring in every game this season to reduce the arrears, Ed Scragg over soon after for the visitors.
Bishop’s regained the lead through Jake Morris, only for Harding to double up for 22-20.
Dalrymple regained his range after Archie Holland dotted down, meaning Morris’ second was only enough for two home bonus-points.
More home misery for Park, Sale success
Rosslyn Park lost a third straight home game, Tonbridge Juddians victorious 17-12 under the Friday Night Lights.
A Charlie Walker try for Park were the only points of the opening half, TJs taking command after the break as Lewis Gjaltema, Jimmy Staples and Tom Mannix crossed, Sam Evans converting the last.
Rosslyn gave themselves hope midway through the final quarter, Steffan James adding to Max Fraine’s try, but it was not enough.
Fifth-placed Sale returned to winning ways with a 29-13 home success versus Sedgley Park.
Joe Green converted a Pete Vickers try to put The Dogs in front, and after Oli Glasse struck a penalty, repeated the trick following Nathan Langdon’s effort.
Ben Gregory touched down for Sedge, but a Fergus Mulchrone seven-pointer made it 21-8 at the break.
A Joe Gilmore score sealed the bonus-point before Green struck a penalty, Rhys Henderson with a late consolation for the visitors.
Moseley march on at bottom side Leicester
Resurgent Birmingham Moseley made it three straight wins with a 28-19 victory at Leicester Lions.
Jack Jolly converted two Ollie Stedman tries before the hosts crossed through Cameron Scott.
It was 21-5 at half-time thanks to Ben Pogson and Jolly, but Leicester cut the gap through Fin Ogden and the boot of Theo Mannion.
Tighe Maxwell-Whiteley converted a Morgan Dawes try for Mose, Liam Burrows’ reply for Lions not enough.
Rams, meanwhile, lost 31-25 at Dings Crusaders.
