Less than a week out from the Australian Open, organisers are scrambling to cope with hazardous smoke about Melbourne Park, with one player forced to retire mid-match.
Slovenian Dalila Jakupovic was leading her round-one qualifying match against Switzerland's Stefanie Voegele, when she collapsed to her knees with a coughing fit.
Ranked world No.180, Jakupovic was a set up and one point away from a tiebreak in the second set, when she suffered the breathing difficulties and subsequently withdrew from the match.
The first day of qualifying was delayed and practice suspended, as Melbourne's air quality ranged from hazardous to poor on Tuesday morning.
Play eventually began at 11am - an hour later than scheduled - after the city's air was the worst quality in the world overnight, due to the bushfires in the state's east.
The smoke is an obvious concern, with the world's eyes glued on Melbourne during the two-week championship from Monday.
Thousands of international visitors and Australian tennis fans will also throng to the precinct.
Health authorities expect the air quality to bounce between the "very poor to hazardous range" until at least Wednesday night.
Tennis Australia boss Craig Tiley said, when it became obvious smoke could have an impact, officials had to act for the welfare of all involved - players, fans and staff.
TA will work with their medical team, the Bureau of Meterology and Environment Protection Authority Victoria scientists, when making decisions about whether player health.
"This is a new experience for all of us in how we manage air quality, so we have to listen to the experts," Tiley said.
"We have now real-time raw data that we can collect - we have installed measuring devices on-site for air quality."
TA chief operating officer Tom Larner said any smoke stoppages would be treated in the same way as an extreme heat or rain delay.
"We will stop if conditions become unsafe based on medical advice," he said.
Novak Djokovic spoke out about the situation last week, saying organisers would be forced to create new rules to deal with smoke.
"People from my team have spoken to Craig Tiley," said Djokovic, who is also ATP Player Council president. "They are obviously tracking the situation every day, as it is evolving,"
Twenty-two Australians are taking part in Open qualifying, including former world No.17 Bernard Tomic.