Newport defeated Pontypridd by 34-23 at Rodney Parade to give themselves one last chance of taking the Welsh/Scottish league title, but they have to rely on Cardiff preventing a Llanelli win on Friday evening.
Newport, with several players missing through injury, beat a makeshift Pontypridd side, whose eyes were more on the forthcoming Principality Cup and Parker Pen Shield finals.
The try-count was 4-3 to Newport, though it took a try in the final minute by no.8 Andrew Powell to finally kill off a splendid Pontypridd effort.
Matt Mostyn, again having to play at centre, Ben Breeze and Jason Forster had scored the earlier Newport tries, while Shane Howarth landed all four conversions as well as a penalty and full back Mat Pini dropped a goal.
Sonny Parker came on as a replacement to score one of the Pontypridd tries with scrum half Gareth Baber and wing Gareth Wyat supplying the others and Nicky Little kicked two penalties and a conversion.
There were yellow cards for Breeze and his Pontypridd opponents Sven Cronk and Matthew Rees in an exciting match well controlled by Paul Adams and before a crowd of around 5,000.
Newport play their last match against Bridgend at Rodney Parade on Saturday (5.30pm), while Pontypridd will then be entertaining Edinburgh at Sardis Road (2.30pm).
The last five years have been an emotional rollercoaster on and off the pitch for RGC1404. Promotion to the Principality Premiership was the culmination of five years of hard work and investment in North Wales. WRU TV caught up with prop Joe Simpson, who was one of the first intake of WRU North Wales Academy players in 2010.
Ebbw Vale captain Damien Hudd picked up the biggest accolade of the night at the 11th Principality Premiership Awards Evening held at Principality Stadium, after leading his side to the title for the first time.
Wales assistant coach Robin McBryde is predicting a tough battle against England on Sunday despite the fact they may not be considered to be at full strength. Players will be out to impress Eddie Jones which makes England a dangerous proposition, he says.
Wales U20 captain Tom Phillips and performance psychologist Dr Rich Neil explain why spending three days at Monmouth RFC has further strengthened the togetherness of the squad ahead of the #WorldRugbyU20s