The Spirit ran in eight tries but had to overcome a powerful Kauri pack, which threatened early.
The answer was to get the ball wide and the home side signalled their intentions with a breakout try.
They had been pinned deep in their own half for about 10 minutes. But rather than boot for touch and get in some more tackling practice, they ran it out from their 22.
It was a plucky but trademark move consistent with the team’s character.
Naomi Sopoaga made a strong carry and openside Sarah Jones brushed off some tacklers.
They worked the ball up field and hooker Tegan Hollows burst on to a short pass and scored.
A new game seemingly broke out and one where Otago dominated.
They looked for width at every opportunity. That stretched the big Kauri pack and Otago were rewarded when talented centre Sopoaga slipped through in the midfield, and again when winger Jamie Church finished off in the corner.
The visitors were down a player. First five Timara Leaf had picked up a yellow card following a string of infringements from her side in the lead-up to her binning.
Once she returned, the game changed again.
Northland got back into the game through a pushover try to No 8 Hikitia Wikaira on the half-hour mark.
The Kauri piled on more pressure late in the half. They were held up over the line twice before lock Tuira Stowers crashed over out wide.
Otago built on their 19-10 lead with a try to Hannah Norris early in the second.
They shovelled the ball quickly to the right winger, who just had to catch it and dive over.
Otago took a turn with 14 players when Hollows was binned 15 minutes into the second half.
Northland struck immediately. They attacked down the blindside from a scrum 15m out and replacement back Hazel Stolz strolled in.
But Otago swung on to attack from the restart and, after several dips at the line, it was Jones who eventually barrelled over.
Hollows returned from the naughty step and barged over in the corner. Otago had swung the ball left and then back to the right to create the opportunity.
The captain Greer Muir helped complete a marvellous win. She exploited a gap at the ruck and took off.
She was nabbed just short but got the ball to Sopoaga to score.
In the other Championship games, Tasman dispatched Taranaki 48-25 and Wellington beat North Harbour 28-10.
In the Premiership, Canterbury cruised to a 62-21 win against Counties-Manukau, Auckland destroyed Bay of Plenty 104-30.
