Last season’s beaten finalists Merthyr, who are second in the table, face fourth placed Cross Keys at Bargoed, while top of the table Pontypridd take on Newbridge at The Gnoll.
While they trail Ponty in the league table at the moment, Merthyr do have two games in hand and are nine points behind. They are due to meet at Sardis Road on 22 March.
By then the cup finalists will be known, with Newbridge hoping to upgrade from their Division 1 Cup final win over Nant Conwy in 2023. They are the only team remaining in the final four who has failed to win the Premiership, or old WRU Challenge Cup.
Ponty and Newbridge met at this stage of the competition some 13 years ago, on Saturday 14 April 2012 at Cardiff Arms Park. In a close-fought encounter it was Ponty who just edged the game by 28-24.
Newbridge have fallen twice to their semi-final rivals this season. They went down 22-0 at Sardis Road in the Premiership and were beaten 30-22 at home, despite outscoring their visitors by four tries to three.
Merthyr have former skipper Craig Locke back among their replacements. He has already appeared in a record eight cup finals and is pushing for another one before he hangs up his boots.
Among the Cross Keys replacements, Connor Hughes will make his 100th appearance for the club if he comes onto the field.
There are also semi-finals in the Division 1 Cup, with Bridgend Athletic meeting Hendy at Tonmawr RFC and Skewen taking on Caernarfon at Llanidloes RFC.
Pontypridd: Dale Stuckey; Stuart Floyd-Ellis, Garyn Smith, Ioan Evans, Joe Davies; Jaydan Pugh. 9. Lucus Welch; Ben Stephens, Rob Jones, Garyn Daniel, Mitch Barnard, Kris Parker, Lloyd Riley, Cally James (captain), Joe Miles
Reps: Jeff Young, Ben Drew, Morgan Bosanko, Oliver Lewis, Aled Evans, Joel Raikes, Oli Shepherd, Louis Rochefort-Shugar
Newbridge: Robbie Turley; Sam Watkins, Josh Thomas, Iestyn Martin-Lloyd, Cian Jones; Simon Veall, Matthew Davies; Gareth Young, Stuart Vokes (captain), Jordan Reames-Williams, Lloyd Ford, Gavin McDonnell, Garin Price, Luke Morgan, Mike Preece
Reps: Joel Gilbert, Michael Kavanagh, Jakob Duffy
Merthyr: Jacob Lloyd; Finley Baker, Cole Swannack, Rhys Davies, Adam Hopkins; Ben Jones, Dafydd Land; Callum Lewis, Ellis Shipp, Rhys Lewis, Paddy McBride (captain), Aled Evans, Kerith Lloyd, Kian Evans, Lennon Greggains
Reps: Ryan Hughes, Travis Hawkins, Callum Dawe, Craig Locke, Dan Phillips, Sam Cross, James Soanes, Tom Hughes
Cross Keys: Ben Roberts; Ralph Miller, Tom Sullivan, Duan Thomas, Laurence Donnelley; Rhys Jones, Tom Bridge; Jake Wiesniewski, Nathan Huish, Richard Cornock, Kieran Lewis, Jon Verrier, Sam Llewelyn, Louis Pullen, Corey Nicholls (captain)
Reps: Connor Hughes, Rhys Hunt, Tom Burnham, Josh Wall, Will Morgan, Elliott Martin-Drew, Ben Murphy, Adam Tetley
