Tom Davies, Ben Griffin and Sam Jones scored for Brecon who now go to Bedwas in the quarters. Jake Newman kicked two conversions and three penalties., while Andrew Pritchard went over for Bonymaen who were also awarded a penalty try and had 11 points from the boot of Lawrence Thomas.
Elsewhere, Crymych beat Maesteg Quins 33-24, while Ystalyfera turned a 13-12 interval deficit into a 24-23 home win over Newcastle Emlyn. Trebanos won 26-19 against Dunvant, making it four wins on the bounce after starting the season with four defeats.
George Sheppard and Josh Ferriman notched tries and Rhys Harris kicked two conversions and four penalties for the home side.
In Championship East, Ystrad Rhondda remain five points clear but were pushed all the way by plucky Penallta, running out narrow 28-27 bonus-point victors.
Jarrad Llewellyn scored twice for the league leaders, who also had Josh Williams and Alex Webber on the scoresheet as they made it seven wins from eight this season. All four tries were converted by Rhys Truelove.
Lewis Stevens, Lewis Barnett, Max Hooper and Daf Rees were the Pitmen’s scorers as they secured two points despite defeat. Stevens kicked two conversions and a penalty.
Nearest challengers Bargoed were inspired by a stunning hat-trick from wing Morgan Powell in their 28-14 home win over Cardiff Met. Ollie Andrews also scored a try and Josh Prosser kicked eight points.
Steff Davies and Liam Antrobus scored tries for the Archers, both of which were converted by Ross McKay. Bargoed remain second, five points behind Ystrad Rhondda with a game in hand.
Third-placed Newbridge also took maximum points from a 36-23 triumph at Bedwas, and are nine points off the summit with two games in hand. They had Cian Jones’ brace and a penalty try double among their scorers, with Stuart Vokes also going over. Sam Watkins added two conversions and a penalty.
Glamorgan Wanderers were 33-16 victors’ over Treorchy, Cross Keys edged out Rumney 19-18 thanks to three Adam Tetley penalties and a Nathan Huish try, while Beddau won 43-22 at St Peter’s scoring six tries.
Cody Baker scored twice, while Tom Edwards and Ewan Parsons both notched their first tries for the Club. Ewan Roberts and Ethan Coombes were also on the scoresheet, and Callaghan Smith kicked 13 points.
