Lachie Kennedy runs 10 seconds flat in 100m in Perth

Lachie Kennedy has set his sights on becoming the fastest Australian sprinter of all time after posting a sizzling 10 seconds flat at the Australian Athletics Championships in Perth.

Kennedy entered the meet at the WA Athletics Stadium with a personal best 100m effort of 10.03 seconds and with the goal of breaking the 10-second barrier in Perth.

Gout Gout set tongues wagging on Thursday night when he posted two 9.99 second runs in the Under-20 100m sprint - both of which were achieved with an illegal tailwind.

It means Gout's official best remains 10.17.

Just 24 hours later, Kennedy blitzed the open men's field in his first-round heat on Friday with a time of 10.00 with a legal 0.9 m/s tailwind.

Remarkably, Kennedy achieved the time without pushing his body to the max.

The current Australian men's record is the 9.93 seconds set by Patrick Johnson in Mito, Japan in 2003, with Kennedy now ranking second with his 10.00.

Rohan Browning (9.96 seconds) and Gout (9.99 seconds) have broken the 10-second mark, but only with illegal tailwinds.

Kennedy, who will run in the semi-finals and final on Saturday, now has his sights set on the Australian record.

"It feels pretty good. Hopefully I can be the quickest ever by the end of the week," Kennedy said.

"Andrew (Iselin) my coach was telling me to give it everything, because he thought it was going to be the best conditions.

"But I really want to save all my juice for the final, because I want the final to be intense.

"I might have subconsciously shut off. Like I was staring at the clock with 30 metres to go, and I was like, 'I might actually get this'.

"With a dip, it could have been nine, but I've got two more races to do that."

On a lightning-fast night in Perth for the 100m heats, Rohan Browning posted a wind-assisted 10.07, Sebastian Sultana recorded a legal 10.12, and Calab Law posted a wind-assisted 10.13.

Jack Hale also put in a promising display with his legal time of 10.23.

Kennedy and Gout will go head-to-head in the 200m on Sunday in what is shaping as another mouth-watering event.

Gout broke Peter Norman's 56-year-old Australian 200m record late last year when he clocked 20.04 seconds - a time faster than Bolt ran at the same age (20.13).

But Kennedy caused an upset last month when he posted 20.26 to beat Gout by four tenths of a second at the Maurie Plant Meet in Melbourne.

"I'm definitely looking forward to it. We have a great rivalry," Gout said ahead of Sunday's re-match.

"And being out here in Perth, it's a great track, so couldn't be happier."

Kennedy says he will definitely contest his 200m heat on Sunday, but will see how his body is feeling before deciding whether to back up for the final two hours later.

In the women's 100m heats on Friday, current national record holder Torrie Lewis and Bree Rizzo both posted 11.25, while 17-year-old rising star Leah O'Brien (11.31) and Mia Gross (11.33) were also quick.

Three-time Olympian Peter Bol eased his way into the 800m men's semi-finals by winning his opening-round heat in 1:48.97.