The Giants led by nine goals at three-quarter time, but collapsed in the final term to lose by one, 55-54.
The Vixens were untouchable in the final quarter, shooting 17-7 to complete the comeback.
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Vixens goal shooter Mwai Kumwenda was in scintillating form shooting 36 from 37, while goal-attack Rahni Samason shot 13 from 15 and three super shots.
The last few minutes of the match were frantic – when Rahni Samason drained a super shot with about five minutes left, the scores were level.
With just seconds to go, it was Kumwenda who gave up possession while trying to advance her position in the circle.
Luckily for her, goalkeeper Emily Mannix saved the day when she made an intercept down the other end of the court.
Kumwenda was able to redeem herself and put the Vixens in front with under 10 seconds remaining.
The ball was quickly moved down the other end of the court, but the whistle beat Sophie Dwyer’s drained super shot, and the Vixens – who were wooden-spooners in last season’s comp – were through.
They will travel to Perth and play the West Coast Fever in the Final next Sunday.
“That was unbelievable. We put ourselves in a shitty situation, so to see that pride and hunger in the end, we knew we were going to go all the way to the end,” Vixens co-captain Liz Watson said after the match.
“I’m so proud. We’ve had such a great season and we’ve worked so hard all season to get ourselves a double chance — which we obviously needed from last week’s performance (against the Fever).
“To finish top it would have been so disappointing to bomb out today, so I’m excited for next week.”
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