The title should be settled on Wednesday evening at the Gnoll when the Welsh All-Blacks take on Bedwas, but if they did lose, they face a hard task at Rodney Parade on Saturday before playing Swansea away on a date still to be decided.
Swansea failed to hold Newport and after leading for long periods they went down 29-20 though both clubs had injury probems and Newport's Canadian international Rod Snow was given a fond farewell.
Aberavon needed a boost from replacement fly half Jamie Davies to defeat Bedwas 21-14. Trailing 14-0 Davies revitalised the Wizards by converting two tries and notching a last-gasp winner that he goaled from the touchline.
Caerphilly departed from the Premier scene with a splendid 36-22 beating of Pontypool and both Pontypridd and Llanelli tuned up for the Konica Minolta Cup final as the Scarlets beat Newbridge 47-22 aided by 27 points from Ceiron Thomas and Ponty won 38-13 at Llanharan as Paul John scored a try against his father's club.
Cardiff gained a good 17-16 win at Carmarthen Quins and Cross Keys had Darren Miles in fine form as they held back Bridgend by 22-12.