The Australian Open practice was temporarily suspended on Tuesday and the rating was delayed one hour due to the poor air quality in Melbourne caused by the ongoing wildfires.
Organizers said conditions were expected to improve and would be “constantly monitored.”
It is estimated that 10 million hectares (100,000 square kilometers) of land have been burned since July 1 amid record temperatures and drought months.
At least 28 people have died.
The classification was scheduled to begin at 11 am local time (00:00 GMT) with British players Liam Broady, Naiktha Bains, Harriet Dart, Jay Clarke and Samantha Murray scheduled on the court.
However, at the time before the scheduled start time, the air quality around Melbourne Park was recorded at 229 in the Air Quality Index, which is considered “very unhealthy.”
“More decisions will be made based on the data in situ and in close consultation with our medical team, the EPA Victoria Bureau of Meteorology and scientists,” organizers said in a statement on Twitter.
“As always, the health and safety of our players, our staff and our fans is our priority.”
The tournament starts on January 20.
Last week, organizers said they were not expecting delays, and tournament director Craig Tiley said the forecast was good.
On Monday, the International Tennis Federation, Wimbledon and the US and French openings donated $ 400,000 (£ 308,000) to Bush’s fire relief efforts in Australia.
Several players have already promised personal donations for relief efforts as part of the # Aces4BushRelief campaign, while the ATP is donating £ 383,000.
Serena Williams donated her winnings after winning the Auckland Classic, and she along with Rafael Nadal, Roger Federer and local favorite Nick Kyrgios will participate in the Rally4Relief exhibition in Melbourne on Wednesday to raise money before the Australian Open.
Former Australian cricketer Shane Warne raised more than £ 500,000 by auctioning off his ‘baggy green’ cap, and he and former Australian captain Ricky Ponting will captain opposite sides in a special Twenty20 game on February 8.