After a rollercoaster ride through the top matches, a birdie by Victorian No.1 Julienne Soo on the 17th won her match with Hannah Green 2&1 to seal the 3.5-2.5 victory.
Remarkably, it left Victoria on the verge of an historic clean sweep of all four teams "“ men's, women's, boys and girls "“ winning national championships in the past month.
The Victorian men will face Queensland at Huntingdale tomorrow morning with a shot to complete the unprecedented sweep.
But for today, the glory belonged to the women, coincidentally captained by the winning girls' team manager Jo Charlton.
WA had been the yardstick earlier the week on the East Course, until the turning point came when Soo stormed home to beat Australian No.1 Green in the preliminary rounds on Tuesday afternoon.
The win gave Victoria top spot and needing three points from six matches today to win the Gladys Hay Memorial Cup "“ and for much of the day that target was in the balance against the tight-knit West Australians in their fifth consecutive final.
But, as they had done all week, the Victorian middle order dug deep when it mattered.
Jess Whitting's win in the No.7 match for WA was negated by Bianca Ling's for Victoria at No.6.
And it looked like Grace Daniell would add another early point for the hosts when she had Alysha Ahnantakrishnan dormie three.
But the WA youngster fought superbly to take the match up the last hole before Daniell prevailed 1-up to remain unbeaten for the week.
Olivia Kline, with grandfather Bill on her bag, fought an epic tussle with WA skipper Hayley Bettencourt who had a chance to win on the last after a ripping approach inside 2m.
But when her putt lipped out, the five-time veteran of this event and the self-professed "mother" of the young squad at age 20, was emotional realising it might be her last time "“ and that WA's chances of reaching 3.5 points were fading.
Kline, who plays at nearby Victoria GC, was typically competitive in pocketing the half-point that left her state on the brink of victory. Remarkably four of her six matches this week were decided on the last hole, and one other on the 17th for the tenacious youngster.
With Charlton and Hira Naveed square playing the last, Soo sized up a 6m downhill birdie try on the 17th, unaware that a two-putt would seal Victoria's win.
The emerging Woodlands star calmly rolled in the putt and shrieked in delight at having toppled good friend and rival Green twice in three days.
"I'm really excited to have done that "¦ and been part of that team," said Soo, whose calm birdie to halve the 16th after Green made a bomb typified the quality of their encounter.
"Looking back, the run on Tuesday (of five consecutive birdies) turned out to be pretty important "¦ to get us on top.
"But it's everyone; all the girls played their part to get us here. It's a fantastic team to be part of."
Naveed, in the midst of Year 12 studies, showed she'd be a player of the future with her conceded par up the last good enough for a 1-up win and to make her the only player other than Daniell to remain unbeaten in all six matches this week.
Charlton was thrilled with the unity of her team, coached by Darren Cole and managed by Tamara Hyett.
"Everyone played their part this week. We all listened to what "˜Coley' and "˜Tam' said and took it out on the course and put it into play "¦ that's really important when the pressure is on," Charlton said.
The win was Victoria's 20th overall, second only to New South Wales' 36.
In the consolation matches, Queensland took third with a 3.5-2.5 win over a gallant South Australian combination, while New South Wales was too strong for Tasmania, winning 5-1 to finish fifth.
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