Auckland came with a point to prove, after going down to the Volcanix two weeks earlier, and they spent the opening 10 minutes camped in Bay of Plenty territory.
However, the home side defended like their lives depended on it and kept Auckland at bay.
Having worked their way into the game the Volcanix went on the attack.
Awarded a penalty right in front of the posts, they opted to go for goal. First five Renee Wickliffe split the sticks and gave her side a 3-0 lead.
The battle for dominance was a fierce one, but for much of the first half the Volcanix looked in control.
With five minutes left in the half, they looked certain to score with a big overlap on the right, but Auckland produced a monstrous tackle to knock the ball free as flanker Kendra Reynolds charged for the line.
Minutes later they were on the attack again and this time the Volcanix did extend their lead. Wickliffe, who was pushed into first five late due to an injury to Ora Williams, split the defence with some of her signature elusive footwork.
She drew the last defender before putting flanker Lesley Elder in for a try. Bay of Plenty led 8-0 at the break.
The Volcanix got straight back into their work and had their second try within the first minute of the second half.
Captain and inspirational leader Christie Yule made a break up the middle into the Auckland 22m.
The defence was scattered and a few phases later fullback Sapphire Tapsell drove over in the corner. The Volcanix led 13-0.
Minutes later Tapsell was in again. The ball came loose inside the Volcanix 22m and Tapsell scooped it up before racing 80m to score. The conversion was unsuccessful and Bay of Plenty led 18-0.
Just as they did in the corresponding fixture at Eden Park, Auckland stayed in the fight.
Ten minutes into the second half they had their first points when, after several phases on attack, they drove over from close range to reduce the deficit to 18-5.
Auckland were gaining momentum and 17 minutes into the second half they were in again, this time through flanker Joanna Fanene, and trailed 18-12.
The Auckland comeback continued and with 18 minutes left in the half they had their third try. The conversion was unsuccessful and the Volcanix were clinging on to an 18-17 lead.
With 15 minutes left to play Auckland's Fanene was sin binned and the Volcanix wrestled back the momentum.
They were patient in attack and it was not long before Elder charged through a gap for her second try. Wickliffe converted and Bay of Plenty led 25-17 with 10 minutes to go.
Auckland scored again in the dying minutes, but it was not enough to change the result or prevent their relegation to the Championship, with the Volcanix running out 25-22 winners.
After the game, two-try hero Elder said the win felt "unreal".
"It was hard, we knew it would be an 80 minute game, we knew it would be physical. We just had to front it, ride it out, spread them and be patient. I'm so proud of the girls.
"We know we are capable of some good stuff and we know we are capable of competing in this division. We wanted to prove that beating Auckland the first time wasn't a fluke, we knew we could do it."
Elder was pleased to end the season with a couple of tries, but credited her teammates for getting her across the line.
"I don't score a lot of tries, so to get two in one game – I don't think I've ever done that before. It's just a tribute to the hard work and the go-forward the girls create."
