Athletic beat Pontyberem 14-3, while league leaders Dunvant had their game postponed due to the bad weather, and second-placed Loughor could manage a 3-all draw at home with Corus.
Carmarthen back-rower Nick Morris grabbed the only try of a dour game, and there were only two first-half penalty goals to trouble the scorers at Loughor, where Peter Smiriglia and Rod Williams exchanged goals in a costly draw for the home side.
Felinfoel crept further away from the highly competitive drop zone with their impressive 28-9 home triumph over fourth-placed Banwen, while Gorseinon jumped to fourth from bottom with their 27-12 home win over Kidwelly.
Penclawdd became only the second team to travel to north Wales and beat last season's northern champions Llangefni in the league this season as they ran out 23-9 victors. The first v third clash in Division 3 West moved Penclawdd 11 points clear of Llangefni.
Newcastle Emlyn made it 20 straight defeats for Hendy as they beat the basement side 22-0, while Lampeter sneaked a 10-7 verdict at
Laugharne to leap-frog Pembroke Dock Quins in the table following their 17-10 home defeat by Aberystwyth.
The top four sides in Division 4 West all came out on top to ensure the battle for the title will continue to the end of the season. Leaders Portarddulais were comfortable 25-5 winners over bottom-of-the-table Llandybie at home, second-placed Ammanford were too good for
New Dock Stars, winning 22-7 on the road, and third placed Llandeilo beat Cardigan 15-3. Neyland remain in the hunt in fourth, 11 points off the leaders, thanks to their 24-0 away win at Crymych.
The battle for the title in Division 5 West continues with leaders Llanybydder putting Furnance to the sword 55-0 and their nearest rivals Burry Port doing almost the same at home to Bynea, winning 32-0.
In Division 5 South-West, none of the top six sides picked up a victory on a day of rain-induced shocks. League leaders BP Llandarcy suffered only their second defeat with a 28-27 reverse at Neath Athletic, while second-placed Ystradgynlais drew 0-0 at home with Porthcawl. Fourth-placed Cefn Cribbwer were beaten 15-8 at Cwmgwrach.
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