Twelve years after becoming the youngest-ever discus world champion, Dani Stevens has called time on her long and decorated athletics career.

Stevens burst into global prominence at the 2009 world titles in Berlin when she won discus gold aged just 21.

No male or female thrower before or since had achieved the feat at such a young age.

She was an ever-present figure on national teams for more than 15 years and courageously overcame a serious neck injury to contest a fourth Olympics in Tokyo in 2021, equalling the record by an Australian track and field athlete.

Stevens's impressive list of achievements included gold and silver medals at the world titles, back-to-back Commonwealth victories in 2014 and 2018 and 14 national discus titles.

She is also one of only nine athletes to have world titles at youth, junior and senior level — an exclusive group that also includes Usain Bolt, Russian pole vault queen Yelena Isinbayeva and fellow Australian Jana Pittman.

"I had always said that as long as my mind and body were able to, I would keep going, keep training and keep competing internationally," said the 33-year-old Stevens.

"I took the time a few years ago and decided that I wanted to compete at the Tokyo Olympics for my fourth Games, and I've been doing things so meticulously, from training, to nutrition and sleep.

"I've gotten to the point where I am really content and happy with everything that I've achieved in my athletics career and feel that now is the right time to step away."

Stevens's best Olympic campaign was in Rio in 2016 when she finished fourth, missing out on the bronze medal by just 44cm.

The following year she won silver at the 2017 world titles in London behind her long-time Croatian rival Sandra Perkovic with a personal best of 69.64m.

That massive throw would have been good enough to win gold at any of the previous 12 world championships or past five Olympic Games.

Stevens was forced to undergo spinal surgery in early 2020 after shattering the C4/5 disc in her neck in a gym accident.

After 14 months of rehabilitation, Stevens returned to action and booked her spot on the Australian team for the Tokyo Olympics, where she bowed out in the qualifying round.

Stevens paid tribute to her coach Denis Knowles, who has been her mentor ever since she first took up the sport in Little Athletics.

"He has sacrificed as much as I have, if not more when it comes to time away from family and all that goes along with it," she said in a statement.

"Denis has been there for me at all times, through the highs and lows of not just athletics but of my life.

"We are closer than most athlete and coaches and I believe that's why we have been so successful."

AAP