Melbourne - Practice sessions for the Australian Open were disrupted by bushfire smoke on Tuesday, just days before the first Grand Slam of the year which begins on Monday.
The crisis has already cast a shadow over Australia's summer of sport. Here are five events that have already been affected by the fires.
Rally Australia, the final round of the 2019 FIA World Rally Championship, was cancelled in early November because of dozens of bushfires raging near the Coffs Harbour venue in New South Wales.
Drivers and crews had feared if the rally went ahead it would be in impossible conditions for officials, teams and spectators even though the schedule had been scaled back.
"Considering the best interests and safety of everyone involved in the rally, and of course the wider community, it is not appropriate to conduct the rally," event chairman Andrew Papadopoulos said.
Australia seam bowler Peter Siddle was treated for smoke inhalation after a Big Bash League Twenty20 cricket match in Canberra was abandoned just before Christmas.
Sydney Thunder and Adelaide Strikers were forced off when the pitch was enveloped in a thick soup of toxic haze. "It was pretty unsafe out there" said Strikers captain Alex Carey.
"We had a couple of cases after, the doctor had to come in and assess (Siddle). We have a few asthmatics in the team as well, luckily they did not stay out there too long."
Siddle, who bowled two overs in the match, made a full recovery.
Matt Jones complained of stinging eyes and trouble breathing on his way to winning golf's Australian Open early in December as smoke from fires raging across New South Wales wafted across the Sydney venue during the first two rounds.
"It's tough to see your golf ball when you're out there playing, where it finishes. Your eyes do burn," said Jones, while New Zealand's Ryan Chisnall, who is asthmatic, played in a mask. Australian No 1 Adam Scott was another to suffer.
"It feels like I should shove a bit of saltwater up my nose or something and try and rinse myself out," said the 2013 US Masters champion and former world number one Scott.
The SOLAS Big Boat Challenge - a warm-up for the famous annual Sydney-Hobart race - was cancelled in December after thick smoke sent visibility plunging on Sydney Harbour.
"The smoke from all the fires is just so severe here on the harbour that you just can't see anything, so it's just too dangerous," Sydney to Hobart Race media director Di Pearson told AFP. "The vision is just so poor."
It was the first time the challenge, which was celebrating its 25th anniversary, had been cancelled.
A new year challenger circuit tennis event in Canberra was moved to Bendigo near Melbourne after the city became shrouded in smoke from neighbouring New South Wales.
British number six Katie Swan complained she had to wear a mask even indoors. "When the sun came up you could see that outside was completely covered in smoke, and ash had settled on top of cars in the street," Swan told the BBC.
"It was like being at a bonfire, but being stood next to it all the time."
City native Nick Kyrgios, who has pledged Aus$200 (US$140) for each ace he serves to support victims of bushfires, said: "My hometown is Canberra and it's got the most toxic air in the world. That's sad. It is tough."