Blackwood opened up the title race in Division One East after edging their top of the table clash with Newbridge.
The Red, Black and Ambers toppled the league leaders at the Welfare Ground after tries from David Briggs and David James clinched a dramatic 12-8 victory.
The Newbridge advantage at the top of the table is cut to just three points and Blackwood's Lyn Hall believes the victory has opened up the division.
"This could be the catalyst for us to push on and to see what the season now holds for us" said Hall.
Leading the chase behind the top two are now Caerphilly, who capitalised on Merthyr's slip-up at Bargoed to take third place following their 22-12 victory over Ystrad Rhondda 22-12. Paul Adams and Stefan Sankala were try scorers for the Cheesemen.
Merthyr fell to fifth in the table after losing at Bargoed, who leapt above their visitors thanks to tries from Matthew Hutcheon and Geraint Hodges.
It took a last-minute try from Andrew Carlson for Rumney to break the deadlock in a tightly-fought 5-0 win over Newport Saracens, while the students of UWIC had no such problems scoring three tries in a 30-0 win at Beddau.
Carmarthen Quins had no trouble in keeping their 100 per cent record in Division One West when they hosted Dunvant.
Tries from Gavin Evans, Andrew Thomas, Alun Davies and two from Jamie Davies saw the visitors routed 27-0.
Quins picked up their sixth bonus point of the season, extending their lead at the top to 19 points.
With Tonmawr in Swalec Cup action, Narberth moved into second spot as captain Steve Martin scored two tries in their 26-15 win at Cwmllynfell.
Corus leapt above Carmarthen Athletic into fourth after beating them 34-15, Maesteg defeated Bonymaen 28-15 and Whitland saw off Felinfoel 18-12.
Welsh players and management joined Deputy Minister for Sport Ken Skates at the Pierhead Building, Cardiff Bay earlier this week to reveal the Union's pioneering school-club hub initiative has been so successful the project will now almost double the scale of the original project.
The Scarlets, Newport Gwent Dragons, Cardiff Blues and the Ospreys look ahead to Judgement Day III which sees the Blues take on the Ospreys (2.30) and the Dragons tackle the Scarlets (4.45pm) at the Millennium Stadium tomorrow afternoon.
Ystradgynlais and Ynysddu played out a titanic struggle at Taffs Well in the SSE SWALEC Bowl semi-final. At the end of the game neither team could be separated after a 15-15 stalemate but Ystradgynlais go through on try count.
Blues strike first in JD III battle - Newport Gwent Dragons lock Andrew Coombs, WRU referee Dylan Llyr Jones and Cardiff Blues hooker Matthew Rees decide dressing room allocations for Judgement Day III
Wales Under 18 captain Calum Haggett has received a conditional offer to read Biomedical Science at St Anne's College, Oxford. WRU chairman Gareth Davies went to meet Calum and Coleg y Cymoedd Principal Judith Evans to wish him luck in his exams and pass on some of his personal experience.
Dodgy tattoos, carthorses, Avatar and soft chins are revealed by Wales Sevens players Tom Williams and Sam Cross as they profile the Wales Sevens squad taking part in Hong Kong this weekend in the latest round of the HSBC Sevens World Series.