It took two field goals, but the Mounties' NSW Cup and Jersey Flegg teams have both progressed beyond the first week of the finals.
The Canberra Raiders affiliates will face a knock-out semi-final in the NSW Cup after Tyler Cornish slotted a field goal with five minutes remaining to give them a 21-20 victory over the New Zealand Warriors at Panthers Stadium on Saturday night.
Earlier in the day, the Mounties under-20s upset minor premiers Newcastle 25-24 in Newcastle with Tobias Westcott's one-pointer in the 62nd minute proving the difference.
It means the Mounties 20s will head straight into the preliminary final, with a grand final berth on the line in two weeks' time.
Young Raiders five-eighth Paul Roache scored one of their four tries.
AT A GLANCE
NSW Cup: Mounties 21 (Brendan O'Hagan, Liam Knight, Sebastian Kris, Mitchell Cahalane tries; Sitiveni Moceidreke 2 goals; Tyler Cornish fiel goal) bt NZ Warriors 20 (Hayze Perham 2, Joseph Vuna, Matiu Love-Henry tries; Chanel Harris-Tavita 2 goals)
Jersey Flegg: Mounties 25 (Hudson Young, Paul Roache, Thomas McGrady, Andre Niko tries; Tobias Westcott 4 goals; Westcott field goal) bt Newcastle 24 (Starford Toa, Beau Fermor, Nash Birch, Tex Hoy tries; Kurtis Dark 4 goals)