SYDNEY (Reuters) - Australian Sally Pearson has not ruled out extending her career until the 2020 Olympics in Tokyo after a hamstring injury ended her hopes of defending her high hurdles title in Rio de Janeiro in August.

The former world champion, who will be 30 in September, felt she had not yet reached her peak as an athlete and scoffed at suggestions the tendon tear she suffered on Monday might bring an end to her career.

"I'm an athlete, that's what I do for a living, I'm not giving up because of an injury," she told reporters in Queensland.

"I know what I'm capable of as an athlete, I don't think I've reached my peak yet, I think I'm capable of a lot more."

Her first priority, she said, was to give her body a rest and thereafter focus on possibly making next year's world championships in London and then the 2018 Commonwealth Games.

The prospect of defending her Commonwealth 100 meters hurdles title in her home city of the Gold Coast was particularly attractive.

"You don't get many chances to run in a major championships 10 minutes up the road from your house. I think it will be pretty special," she said.

Pearson said the injury had come out of the blue and was not the result of over-training as she battled back from the horrific injury she suffered in Rome last year, when she shattered her wrist after a fall at the Golden Gala meeting.

"Everybody pushes their bodies to the limits for the Olympics and it's just a question of whether you tip over the edge," she said.

"Unfortunately I tipped over the edge through my training. Unfortunately these are uncontrollable things. This is what we have to do as athletes.

"The last three years have been frustrating with injuries every single year, it's just my body saying 'give me a break'."

Renowned for her single-minded focus and determination, Pearson said continuing until Tokyo, which would be her third Olympics, was not out of the question.

"I'm only 29, track and field athletes can go on for a little longer but at the moment I'm only looking forward to 2018," she said.

(Reporting by Nick Mulvenney, editing by Amlan Chakraborty)