North Harbour produced a clinical performance to see off Wellington 40-37 and earn a spot in the Mitre 10 Cup Championship final.
In a thrilling contest in Wellington on Saturday, North Harbour - who were up 20-18 at half-time - held on to win their first play-off match since 1994.
Daniel Hilton-Jones proved to be the match-winner at Westpac Stadium, crossing over for a try to split a tie and give North Harbour a 37-30 lead.
It was a lead they never relinquished, despite Sheridan Rangihuna's late try and Jackson Garden-Bachop's conversion
The reward for North Harbour is a showdown against Otago in next week's decider in Dunedin, with the winner to gain promotion to the Premiership.