Glyncoch of Division Six Central have been the surprise package in this season's cup tournaments and they will be the underdogs when they come up against New Tredegar of Four East.
But they will be keen to make it a cup and league double after securing the Six Central league title.
They have punched above their weight in every round, reaching the quarter-final with a thrilling 13-9 victory at Four South West outfit, Glyncorrwg.
Amman United of Four West were the next visitors and this tie was even more tense with Glyncoch edging through 18-16 to set up a semi-final against another Four East side in Talywain.
The Six Central side won through to the Millennium Stadium after a 24-21 victory with three penalties and a conversion from outside half Lee Goddard proving decisive.
"We've been building for the last few seasons and were unbeaten two years ago," said Glyncoch coach David Allen.
"We're unbeaten again this season and hope we can go all the way. We've beaten six Division Four teams this season and they have all been top teams which gives us a lot of confidence. Hopefully we can keep it going. With Ponty here , we're hoping to have very good support."
Division Four East side New Tredegar have kept their best form for the cup, and after two walkovers in the early rounds they defeated Abercarn 19-16 and Abertysswg 9-0. They then travelled to Hafodyrynys in round five where it needed a Ricky Hawkins try and two Craig Thomas penalties to edge through 11-10 against the Five East side.
The quarter-final paired them with Four South West side Resolven but three tries helped the Newts to a 22-17 victory and a meeting with Tycroes in the semi-final. Tycroes have had a good league season finishing in second spot but New Tredegar earned their visit to the Millennium Stadium with a 38-31 success.
The WRU has launched a campaign to create a long term legacy for Welsh club rugby by highlighting the advantages of volunteering. Rhian Edwards, a volunteer at Seven Sisters, has enjoyed many benefits of her volunteering at a grassroots rugby club including being part of the Rugby World Cup volunteer workforce after being nominated by the WRU - and the WRU is asking for more people to develop their 'Welsh rugby roots'.
Wales head coach Warren Gatland and captain Sam Warburton say their first prioirty on Sunday in the opening game of the World Cup is to win against Uruguay and not get overly concerned with points difference.
With only days to go until the biggest rugby competition in the world begins, rugby fans visiting Cardiff this autumn will be able to enjoy a special display at National Museum Cardiff as part of the celebrations surrounding the Rugby World Cup.
Geraint John has taken up the new role of WRU elite coach development manager having arrived in Wales last week. WRU TV caught up with him at the WRU rugby department's strategy day at the Millennium Stadium.