SWALEC League Division Two East leaders Tredegar were given a second-half scare at Ynysybwl.
Tries from flanker David Ford, full-back Robert Smith and winger Daffyd James saw Tredegar build up a comfortable 22-7 before the All Whites rallied to bring the score back to 22-18.
A late penalty from Tredegar centre Greg Jones stopped the tide and saw the visitors emerge 25-18 winners.
Second placed Bedlinog were 22-15 winners at Rhydyfelin, while Mountain Ash crept past Llantrisant 10-6 in the clash between third and fourth.
Scrum-half Merion Thomas scored the game's only try for the Black and Ambers.
With Division Three East leaders Garndiffaith not playing, Pill Harriers moved level on points with the leaders after a five-try win at Nelson.
A pair of tries from Craig Lloyd, plus one each from Mark Wheeler, Louis Culverwell and Mark Thorogood saw Harriers pick up a bonus point which means they trail Garndiffaith on numbers of wins recorded.
Third place Croesyceiliog came back from 20-8 down on 50 minutes to win 28-20 at Rhymney. Matt Entwhistle conversion from his second try five minutes from the end saw the Croesyceiliog s take the lead, with a fourth try from Ieuan Wakefield earning the Cockerels a bonus point, denying Rhymney one in the process.
Llandaff remain top of Division Four East after a narrow win at Rhiwbina. The scores were locked at 13-13 with ten minutes remaining when full-back Nathan Rees kicked a penalty to give Llandaff the lead, which they refused to relinquish.
Nantyglo in second crossed ten times in a rampant 62-5 win over bottom club Pontllanfraith. There was two tries each for Richard Jones, Anthony Williams, Jamie Davies and Chris Williams for the Monmouthshire club.
The top two in Division Five East going into the afternoon, Blaenavon and Abercarn, met at the Recreation Ground, with visitors Abercarn running out 31-12 winners.
Tries from Matthew Jackson, Jack Davies, Nicky Lloyd and Jason Evans saw Abercarn pick up a bonus point, which sees them go ten points clear at the top of the table.Blaenavon's defeat sees them fall to fifth, behind Caldicot, Talywain and Oakdale, who all recorded away wins.
Wales reached their first semi-final since 2013 in the opening round of this season's HSBC World Rugby Sevens Series in Dubai. WRU TV's Graeme Gillespie recaps on what proved to be an eventful tournament
Wales and Ospreys back row James King, who came through the North Wales age grade system, nominated North Wales Regional Community Rugby Manager Marc Roberts, in the WRU's 'Diolch' initiative where squad players thanked those who played a part in their rise to the top.
Beating Merthyr has boosted Carmarthen Quins hopes of reaching a top eight spot in the Principality Premiership. Quins captain Haydn Pugh is delighted with his team's progress and is determined that everyone from the Under 6s through to the senior team, enjoys the ride.
When the Wales squad were asked to nominate individuals who played a big part in their early playing days, Wales and Dragons full back and wing Hallam Amos thought of his former Monmouth School rugby coach John Bevan.
Sam Cross and Luke Treharne have been named as co-captains of the Wales Sevens side as head coach Gareth Williams names his 12-man squad to play in the first leg of the HSBC World Series in Dubai next weekend.
Bedwas head coach Steve Law and players Nicky Griffiths and Alun Rees extol the virtues of the close knit club as they prepare to host third place RGC 1404 - who are one place head of them on the Principality Premiership points table - on Saturday.
Many of the Wales squad have said Diolch (thank you) to someone who played an important part in their early playing days by nominating them to be invited to the Wales v South Africa match. One person, Gowerton Comprehensive geography teacher Mr Dean Mason was nominated by two of his former pupils, Dan Biggar and Sam Davies.
The second WRU disability rugby pilot has been delivered, this time in Caerphilly schools, culminating in a festival at the Caerphilly Centre of Sporting Excellence, Ystrad Mynach tomorrow. Plans are in place to set up a Disability Rugby Club in Newbridge to provide long-term playing opportunities.
WRU TV: Hear from inside the Wales camp as Neil Jenkins discusses this weekend's clash with South Africa and how the squad are looking to put in a strong performance to round of the 2016 Under Armour Series