Takahiwai made their presence felt with early tries, not allowing Moerewa's potent attack to impose themselves on the game as their defence continued their strong 2018 form.
The match was billed as the best defence against the premier attack in the competition but the defensively-stout Takahiwai outfit stopped most of Moerewa's raids.
The win lifts Takahiwai to second on the ladder, three points behind leaders Ōtangarei who enjoyed a bye week following the withdrawal of Northern Wairoa Bulls.
Meanwhile Portland Panthers pipped Hora Hora Broncos at the post in an 82-point thriller.
Hora Hora have picked up just the solitary victory in 2018, though that isn't a great reflection on how competitive they have been at various points across the season.
They looked likely to double their win tally at home but Portland clung on for dear life in the latter stages of the match to extend the gap between themselves and Hora Hora on the ladder.
