Risca booked their place in the semi-finals of the SWALEC Plate after ending Cardiff University's cup dream with a thrilling 48-28 victory.
Risca are now the lowest-ranked side left in the competition, but will surely fancy their chances after a stunning eight try haul.
Tries from Rhys Putter and Rhys Carpenter and David Jefferson helped the home side on their way to a 26-14 half-time lead, but it was in the second period that Risca really turned on the style.
Two tries from number 8 Richard Evans and a try each from Nicky Davies, Owen Cooper and Tim Barnes completed the rout, although the students of Cardiff went down fighting and can be proud of their displays in this season's competition.
Tredegar Ironsides pulled off the shock of the day with a 15-0 win over Nantyffyllon. The Division Four East outfit grabbed a try in each half through wing Lewis Pritheroe and centre Craig Monaghan.
Rhydefelin survived a second-half comeback from fellow Division Two East side Mountain Ash to win 21-15 at Parc Duffryn Pennar.
The away side had lead 15-5 at half-time thanks to two tries from Aled Jones, before tries from centre Adrian Owen and Dale Keppin hauled Mountain Ash back into the game.
Two penalties from Geraint Watts kept the home side at bay to ensure Rhydyfelin's passage into the final four.
In the remaining quarter-final game Ammanford ran in three tries as they beat Newcastle Emlyn 28-15.
WRU chief executive Martyn Phillips hosted the second meeting of the WRU Youth Board last weekend ahead of the Judgement Day IV regional double-header. Tthe board, made up of 15 under-21-year-olds from around Wales, heard presentations from head of participation Ryan Jones, policy and integrity manager Jeremy Rogers and national women's rugby manager Caroline Spanton, with Pro Rugby Wales CEO Mark Davies also on hand to hear the range of views aired.
Wales duo Rhun Williams and Liam Belcher, who makes a welcome return after five months of injury woe, look ahead to next month's World Rugby U20 Championship in Manchester where they will face Ireland, Georgia and New Zealand.
Whenever Bedlinog tackle Penallta a massive fixure is guaranteed but this Sunday there will be even more emphasis placed on the two rivals when they contest the SSE Swalec Plate final at Principality Stadium.
Ahead of their SSE SWALEC Bowl Final clash with Taffs Well at Principality Stadium on Sunday, Burry Port share their #FABXV nomination with WRUTV in the search for Welsh rugby's greatest volunteers. Everyone can get involved by sending nominations via twitter to @WRU_Community using the hashtag #FABXV
Cardiff Blues prop Gethin Jenkins and Ospreys centre Ben John look ahead to the first game at Principality Stadium in Saturday's double header which is promising to be a special occasion for all Welsh fans.
Carmarthen Quins Director of Rugby Ian Jones and committee member Jeff Thomas along with Llandovery chairman Handel Davies look ahead to Sunday's SSE SWALEC Cup showdown where both teams are out to prove 'West is best'
SWALEC ambassador Shane WIlliams is looking forward to Sunday's Finals Day where the Cup, Bowl and Plate offers a great opportunity for players and teams to experience the magic of playing at Principality Stadium
Carmarthen Quins coach Richard Kelly believes it is an exciting time to be part of the Scarlets region as his side take on local rivals Llandovery in the SSE Swalec Cup final on Sunday, as WRU TV's Graeme Gillespie discovers