The Kembla Joggers athlete initially feared for Olympics dream was over after a serious accident in the gym in February.

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Carli was rushed into emergency surgery after she ruptured her carotid artery, an injury typically suffered in motor vehicle crashes.

The operation was a success, however doctors could provide no firm timeline for a return to competition.

Despite the uncertainty, Carli pushed on and followed a painstaking rehab process in a desperate effort to compete at the Tokyo Olympics.

On Saturday morning she achieved that dream when she contested heats of the 400 metres hurdles.

With the top four progressing, Carli finished fifth in a time of 56.93 seconds to narrowly miss a place in the semi-finals.

It's not as fast as her personal best, but given she had just one race before the Olympics, it's an impressive achievement.

"I've had six weeks of full training," Carli told Channel 7. "I did my first race four weeks ago. That time's quite good considering, it's been really hard."

There was early drama before the race, with Jamaica's Ronda Whyte disqualified for a false start.

Carli started fast before fading in the third hundred, as Dutch star Femke Bol cruised to a comfortable heat victory.

The Wollongong athlete finished well and came close to running down Great Britain's Jessica Turner, however it was not to be and her Olympics debut came to an end.

Having had a taste of the action, Carli is determined to push on to Paris and reach her potential.

"When things like this happen, it's so cliche, but it really makes you think about things that are important. To me it's my athletics and give me three years with that kind of mentality and see what I can do."