The visitors repeated that formula to take the lead for the only time of the match before Dargaville kicked into gear to score three times to lead 20-12 at the break.
The hosts scored first after the break through their captain but the gap in score only urged Okaihau on as tough arm wrestle ensued with centre Bradley scoring his second and giving the visitors much needed hope.
However, it was fast-running second rower Siuaki Lisiale who scored next for Dargaville breaking the deadlock to put the game out of reach for a brave Okaihau.
The upset loss to Whangaroa College last week set Combined College on track for their first Grand Final appearance in the Secondary School Finals.
Bream Bay took the long trip to Taipa to go down by two points to the hosts in a close encounter to end their impressive showing in this year's competition.
The young team's progress has been admirable and if the team is able to stick together next year will offer a formidable challenge for the top prize.