Holders KCB will face Nondies in the Impala floodlit final on Saturday.
The bankers weathered a second-half surge from Blak Blad to win 14-3 while Nondies upset Menengai Oilers 16-11 in a pulsating encounter played on Saturday night at Impala grounds.
Nondies, three-time winners of the event, were not given a chance against the Nakuru-based outfit but dug deep to romp to the final.
Frank Mutuku scored the try for Nondies with Ben Sal adding a conversion as Calvine Sheunda kicked over three penalties. Nondies led 6-5 at the interval.
Oilers flanker Christine Shitundo scored a try with Austin Sikutwa and Abdulwalib Wesonga adding a penalty each for the 2019 losing finalists.
KCB outscored the varsity outfit by two tries to nil with Peter Waitere and Brian Wahinya scoring a try each as fullback Isaac Njoroge added two conversions for the win.
Lionel Ajeliti scored a penalty for the students.