Jones, last off, pushed all the way and was on track for an impressive upset but mistimed a stroke on the bottom drop and that was all it took to relegate her to second, just 0.49s behind Fox but more than four seconds clear of third-placed Prigent.
"I watched Jess' run from the top and knew it was two seconds faster than my semi time - I quite like the feeling of having to step up and put something good down," Jones said.
Fox said she relished the chance to cross the Tasman and compete against the flying Kiwi.
"The course is really technical and there are a lot of moves throughout the whole course so you've got to really be positioning well and then attack it when you can and with the wind on top of that, it was quite a challenge," Fox said.
Tauranga teenager Jack Egan held New Zealand's slim C1 hopes in his hands as the only Kiwi to qualify for Sunday's final. Egan, who turned 18 in November, was the sixth-fastest after the semifinals and needed to beat six Australian paddlers in the final to claim the Oceania continental spot for Tokyo.
After a promising start, he struck disaster just after the 16th gate on a blustery Vector Wero Whitewater Park course, when his hand slipped off the paddle and he rolled into a pocket. He missed gate 17 and picked up a flurry of touches to finish 10th.
"I was having a good run and the wind was mostly in my favour but I just got caught out trying to switch from right to left and it was quite costly," Egan said.
"The wind suddenly picked up and it was hard work trying to predict where the gates were going to be but it was still an amazing feeling being in this final, seeing that the hard work has been paying off. This is a stepping stone for me and it was good to be able to give the Australians some competition."
Tasmanian Daniel Watkins picked up the Oceania title with a clean 101.57s run, finishing just 1.77s ahead of Zach Lokken (United States) and 4.55s ahead of another Australian, Ian Borrows.
The C1 women's semifinals and final, and the men's K1 crown were set to be decided on Monday afternoon, with Olympic selection spots also up for grabs for both Australian and New Zealand men.
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