Rhydyfelin ran in seven tries in total to heap more misery on Treherbert who have now lost ten games out of ten in the league this season.
Croesyceiliog beat Nelson 13-7 in the game of the day in Division Three East. Tries from Scott and Hicks saw the home side leapfrog their visitors into second position in the table.
Pill Harriers came out 26-14 winners against mid-table rivals Gwernyfed, tries from Richard Tuck, Craig Lloyd and Matt Williams set the home side on their way, but it was eleven points from the boot of Rowlands that put daylight between the two sides.
Pontypool United gained a comfortable 16-5 win over Cwmbran to end their year on a high, and leave themselves well positioned in the chasing pack.
Llantwit Fardre made it nine wins out of nine with a 13-0 win away at Brecon, and remain top of Division Three South-East.
Treorchy also remain unbeaten after their 27-10 win against St Peters, but closed the gap on the leaders after tries from Andrew Malin, Craig Payne, Gareth Beer and Peter Hutchins, ensured a bonus point.
Jamie Cavell grabbed two tries as Fairwater beat Nantymoel 41-6 and Llanishen kept up their pressure on the leaders with a six try-haul as they smashed Penarth 39-12.