Williams, 39, was set to join world number one Ash Barty, Karolina Pliskova and Naomi Osaka in a strong field at the Queensland Tennis Centre from Jan. 6-12 and the organisers said they would announce a wildcard to take her place in the draw.
"Unfortunately, I won't be starting my season in Brisbane due to an unexpected setback during my training," Venus, a seven-times Grand Slam winner who was handed a wildcard for the event, said in a statement.
"I look forward to being in Australia in the New Year and will see everyone at Adelaide."
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The news follows a disappointing end to last season, in which Williams had failed to progress beyond the second round of a tournament since Cincinnati in August, and slipped outside the top 50 world rankings.
The drop in ranking also poses a threat to Williams' participation in this summer's Tokyo Olympics, as she is currently ranked only eigth highest in the US.
The Adelaide International, where Williams will hope to begin improving on that ranking, begins on January 13 ahead of the Australian Open, on January 20.
Additional reporting by Reuters.
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