Rhuthun travelled to Llangefni hoping to improve upon an ordinary record on Ynys Mon in recent times.
They got things moving in the right direction with some heave ho in the maul from the forwards providing an attacking platform from which Stand Off, Emyr Gwynedd could have launched his outside backs.
However, when the playmaker assessed his options, he chose to fly solo, some overzealous defence from his opposite, opening a gap in the home defence that Gwynedd exploited to open the scoring.
Everytime Cefni's own driving maul was presented with an opportunity to rumble, it posed a threat to an otherwise dominant Ruthin performance.
It was a drive and a well timed splinter movement that got the home side on the ledger. Hooker, Alex Phillips the beneficiary after decent shunting from his fellow forwards.
The score at the break was 5-14 after defensive stalwart, Cameron Lumsden crossed for Rhuthun's second.
Gwion Richards knocked over his second conversion of the afternoon to give the Blues a two score buffer.
After the break with both sides seeking a game defining score, there was a mutual struggle to bring the best laid team talk intentions to life.
Having missed an earlier opportunity, it was a Gwion Richards penalty that gave the visitors the command they so craved on the score board.
It was a case of best until last for the visitors.
As the forwards came marauding round the corner of the ruck, the backs called for the play to be reversed down the short side.
They had their way.
Replacement, Deian Williams fed Emyr Gwynedd with the captain releasing his wing man, Harri Hughes who had the wheels to seal the deal, despite the scrambling efforts home defence.
The victory leaves Rhuthun at the top of the table albeit with unbeaten Llandudno only a point behind with two games in hand.