By the time Tonegato hit the 22m line she put the foot down and raced away to score the try of the tournament so far under the posts.
New Zealand scrambled desperately in defence but were unable to stop the massive Vakurunabili crashing over and giving Fiji first place in the pool.
The main event begins at 12.28 with the quarter finals between Fiji and US followed by South Africa and Kenya at 12:50.
Australia survived two tight matches against the United States (26-19) and Scotland (24-21) to be among four unbeaten teams. Australia then had to survive more than three minutes of stoppage time with only six players after receiving a late yellow card.
After narrowly missing out on a place in the Cup quarter finals on day one, England thrashed Papua New Guinea 52-0 in the semi-final.
Australia's men and women have both performed well on the second day of the 2018 Sydney Sevens, moving towards their respective finals campaigns tomorrow.
The Canadians finished first in Pool C after going 3-0 during the opening day of competition at the 12-nation tournament.
But Quirk says Australia's superb form, which has seen them progress without conceding a point in any of their five games, means they could sleep soundly.
Black Ferns superstar Portia Woodman has taken aim at New Zealand Rugby, after it made the decision to not host a leg of the Women's Sevens World Series in Hamilton this year.
In Pool A New Zealand and Fiji both qualified comfortably for the Cup quarter-finals with wins on Day one and two over Samoa and Russian Federation.
Defensive pressure was a key to Australia's semifinal win on Saturday.
Ahead 12-0 at half-time, the Kiwis extended their lead via Kurt Baker shortly after the restart. "Here in Sydney we are focused on the basics because we know we can punish teams if we play to our game plan".
Woodman tops the try-scoring charts in the sevens world series with 22 - seven more than team-mate Michaela Blyde in second place.