Griquas secured a home final as they beat the Blue Bulls 30-17in their Vodacom Cup semifinal in Kimberley on Friday.
The hosts ran in four tries to set up a final against either Western Province or the Pumas who play their penultimate-round playoff on Saturday.
The visitors dominated territory and possession in the first half but Griquas made far better use of their limited chances.
The home side held the upper hand in the scrums while their defensive effort helped to stymie much of the Blue Bulls' attacking ambitions.
Griquas' opening try was a masterful effort as scrumhalf Jacques Coetzee broke on the Bulls' 10-metre line before off-loading to lock Ligtoring Landman, who fed eighthman Leon Karemaker to outstrip the cover defence and score.
Flyhalf Marnitz Boshoff added a penalty before Griquas extended their lead to 15-0 after 25 minutes when right wing Rocco Jansen charged down a kick from Blue Bulls fullback Ulrich Beyers before following up to dive on the bouncing ball in the in-goal area. Boshoff kicked the conversion.
The visitors, who had 59 percent possession and 76 percent territory in the first half, threw everything they had into attack and turned down four kickable penalties in their search for tries.
Their enterprise was finally rewarded in the dying minutes of the opening period when right wing Sampie Mastriet dived over in the left-hand corner for an unconverted try.
Griquas continued on their merry way in the second half and, 12 minutes after the restart, fullback Francois Brummer scored a converted try after a wonderful off-load from Boshoff.
The Blue Bulls, however, refused to surrender and a two-try blitz from the visitors narrowed the gap to five points after 63
minutes.
Inside centre Jan Serfontein scored a superb individual try when he danced his way past three defenders, while replacement lock Daniel Adongo dived over to dot down after the Blue Bulls had taken the ball through 19 phases.
Griquas made sure of the victory when replacement back Jean Stemmet rounded off a move that Brummer had started deep in his own half.
Boshoff kicked another penalty, for good measure, on the stroke of full-time.
Scorers: Griquas: Tries: Leon Karemaker, Rocco Jansen, Francois Brummer, Jean Stemmet. Conversions: Marnitz Boshoff (2). Penalties: Boshoff (2).
Blue Bulls: Tries: Sampie Mastriet, Jan Serfontein, Daniel Adongo. Conversion: Tony Jantjies. – Sapa