Finally able to clear out of their territory, Marist attacked through a great bust by reserve forward Pania Pari, followed up by first five Rebecca Tamati and No 8 Te Reo Tuatahi Mareikurua, which led to a penalty that talented winger Alice Ireton slotted to narrow the gap at halftime.
Marist had been turning the momentum and completely flipped it to start the second stanza, as a strong break by second five Keisha Campbell brought them onto the attack, with Marist getting penalties and driving at the Kaierau defensive line in threes.
Kaierau fullback Samantha Rees just stopped Campbell short, but the forwards were there along with Munro to burrow over, with Ireton slotting an excellent angled conversion for a 10-5 advantage.
Kaierau began to claw their way back, still making the odd error but swiftly getting the ball back from Marist, towering centre Kara Adrole charging free down the far touchline with only Munro able to stop her.
Yet Kaierau kept working, with Nevanna driving close to scoring, before the ball was freed to hard-working lock Cienna Newland, also denied a try in the first half by Munro, who this time was able to hold off the last tackler to score the equaliser.
Marist then absorbed another deep attack by winger Ashley Hargreaves, getting a penalty, and then Ireton made a dash of her own, leading to a penalty 37m out.
Ireton missed a long 37m penalty attempt, but Marist chased hard and trapped Kaierau in the ruck, this time on the 22m, and Ireton made no mistake the second time to put her side back in front.
Marist’s supporters had found full voice now, and soon they were ecstatic, as a hesitant Kaierau backline made some loose passes from a scrum win, with Ireton pouncing to toe the ball through - kicking it twice more to dive on the ball behind the posts for a converted try and a 20-10 lead.
After an attacking burst from Diaz, Kaierau earned a free kick and took the scrum, leading to Gabriel rampaging through tacklers up the middle, before the ball was transferred wide and this time Adrole got a good pass to dash free and improve the angle for Rees to add the conversion.
With both sets of supporters and the reserve benches screaming encouragement for the last seven minutes, Kaierau had one last chance with a penalty tap, but Marist counter-rucked, then booted it out for fulltime.
Marist 20 (P Munro, A Ireton tries; Ireton 2 pen, 2 con) bt Kaierau 17 (S Beamsley-Wiari, C Newland, K Adrole tries; S Rees con). HT: 5-3 Kaierau.