Two full-blooded Konica Minolta Cup semi-finals saw Llanelli beat Bridgend 20-10 to book a final with Pontypridd, who held off Aberavon 33-13.
Discipline was crucial in both ties, with Aberavon losing on Saturday after having centre Darren Ryan sent off.
It was a similar story on Sunday, where prop Phil Booth's red card for a kick left Bridgend struggling.
Both matches saw mass brawls as tension got to the players, while there was also some exciting rugby played.
Pontypridd held a slim 11-3 win at half-time thanks to a Jason Pocock try and two penalties from man-of-the-match Dai Flanagan, replying to an early penalty from Aberavon's Jamie Davies.
Daran Griffiths and Richard Morris claimed second-half tries for the Wizards, but Ponty stretched away with two tries from outstanding flanker Rhys Shellard, one from wing Richard Fussell, plus 10 more points from Flanagan's boot.
It was even tighter at the break between Llanelli and Bridgend, with the sides tied 7-7.
Llanelli were awarded a penalty try after Bridgend illegally stopped a scrum on their line, Kieron Thomas converting, while wing Grant Epton took Gareth David's chip over the top to open Bridgend's account, David also converting.
Two Thomas penalties gave Llanelli a six-point lead before Booth got his marching orders and the Stradey Park outfit took control.
Bridgend could only muster a David penalty, while Gavin Quinnell emulated big brother and coach Scott by charging over from the base of a scrum for a converted try that sealed the win for Llanelli.