Outsiders ruled the four $10,000 heats in a bizarre night which would have left punters scratching their heads.

Ashlee Grives achieved a double-up of upsets in the 3YO Regional Qualifying Heats (1,730 metres), driving home Peter Trevor-Jones' filly Matamua to victory as a $51 shot before taking her own gelding Romero home as a $9 chance.

The stunning results continued into the 2YO heats when Nathan Turnbull held onto his lead in the colts and geldings race with Substitooth ($41).

Rank outsider Ellen Shannon then delivered the greatest upset of the meeting during the fillies race when Glenn McElhinney steered the $71 hope to victory over stablemate Shannonsideal ($23), giving trainer Peter Bullock literally the most unlikely quinella of the race.

If you put a dollar on a multi containing those four winners then you would have turned it into $1.3 million.

Grives began the strange run of results by taking filly Matamua to her first career win against far more fancied rivals.

With just two placings from 10 starts, for less than $3,000 in prizemoney, there were little to no indicators that Matamua would be worth putting in the winning mix.

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However, one factor in her favour was a gate one start, and Grives used it well to take an early sit behind Negative Nancy.

Most eyes were still fixed firmly on odds-on favourite Navua Girl ($1.95) who settled three back on the outside.

Negative Nancy pinched a comfortable 32.8 second quarter and the pace wasn't to Amanda Turnbull's liking.

Turnbull began a three-wide move on Navua Girl along the back straight to bear down on death seat runner Groovy Shannon.

Negative Nancy refused to give in despite the pressure from Matamua on her outside and Kid You Not on her inside.

Surprisingly Navua Girl couldn't make up the ground on the leading trio and it was left as a three-way dash to the line.

Matamua appeared to find another level across the closing 100m and flew by Negative Nancy for the boilover.

Kid You Not ($6.50) continued her consistent form of late by heading off Negative Nancy ($41) for second.

The winning mile rate was two minutes flat.

"She had the good draw tonight and was back in the fillies class," Grives said.

"She's been racing quite well with no luck. She just got the perfect trip tonight."