Waihora will meet Rakaia on Saturday in the country combined senior rugby final at Tai Tapu Domain.
Waihora held-off Prebbleton 22-15 in the semi-final at the weekend, while Rakaia ended Springston’s fairy-tale run in their debut year 28-16.
Waihora will play their fourth final, their first since 2016, while Rakaia will be in their first final.
Waihora had an attacking edge over Prebbleton, out-scoring them three tries to none.
Only the boot of Prebbleton’s George Wigley kept his team in the contest.
Waihora coach Joff Mooar lamented the lack of discipline, but was happy that their dominant scrum had laid a strong platform.
“I thought Prebbleton really brought it to us and made us battle very hard in the tight exchanges,” he said.
Two tries to Will Hurst and one to Kees Duyvestyn and accurate kicking by Harry Kirk kept the hosts in front throughout.
Mooar praised his team’s defence.
“In a play-off game, you really want your defensive systems to stand up and when we were tested, we really fronted-up,” he said.
Mooar said he expected his team to be favourites for the final, given their four past appearances in the decider and Rakaia’s debut appearance.
“The fact the final is here will be a big plus for us but I expect Rakaia will come here with a sense they have nothing to lose.
The two sides have not met in 2018 but were top qualifiers in their respective sections.
Rakaia always had control of their game against Springston, and in spite of a late yellow card which offered the visitors hope, Rakaia always looked comfortable in home conditions.
•Waihora 22-15 Prebbleton
•Rakaia 28-16 Springston
•Southbridge 21-22 Saracens
•Lincoln 24-26 Darfield
Canterbury Supporters Trophy
•Celtic 23-20 Glenmark-Cheviot
•Southern 20-20 Kaiapoi
•Methven 20-21 Burnham-Dunsandel-Irwell
•Oxford 15-15 Ohoka
•Rolleston 12-28 West Melton
•Hampstead 27-24 Hurunui
•Hornby 25-21 Ashley