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.
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.