Tournament organisers have spared Roger Federer the worst of today's expected extreme heat when he takes on Russian former world number three Nikolay Davydenko in the second round of the Australian Open.
The temperature is expected to hit 39 degrees in Melbourne but the Swiss maestro is likely to commence play in the relative cool of the evening in the opening match of the late session at Rod Laver Arena.
Extreme heat is a feature of the year's first grand slam, and the organisers were forced to suspend matches in the 2009 tournament during a period of scorching weather.
Federer, however, could play in air-conditioned comfort under a closed roof against the 40th-ranked Davydenko, should conditions breach the tournament's tolerance threshold.
The Open's tournament referee has the discretion to put into practice its unique ''extreme heat policy'' and close the roof of the two main courts, allowing play to continue indoors.
Simultaneously the policy demands that players on open-air courts - such as Margaret Court Arena - are removed from the microwave as play is suspended.
Extreme heat is determined, not by the pure temperature, but by what is known as ''the wet bulb'' - a combination of heat, humidity, wind and solar radiation - ie, if it's cloudy, the player has less heat on their back.
Tournament referee Wayne McKewen is the man who decides, in conjunction with his medical team and weather expert, what steps must be taken to protect the wellbeing of players. And McKewen reckons the roof is set to stay open today, because while 39 degrees sounds ugly, the conditions won't be terrible for the players. Humidity is expected to be low.
''What they're predicting tomorrow, it's very low humidity, it's a dry heat ... that makes a very big difference to the players,'' he said.
The tournament has ways to cope with baking days. At a wet bulb of 26, ice vests are sent to all courts. At 30.1 - wet bulb again - women get a 10-minute break before the third set. Then, at this unspecified but obviously very nasty number, the extreme heat policy comes to pass, just as players are passing out.
Andy Murray, six years younger than Federer, will have to sweat it out in the heat as the second match of the day session when he takes on Joao Sousa, a 100th-ranked Portuguese he has never played before.
"I don't know too much about him, but I've seen him play a couple of matches during the clay court season last year in Barcelona," 25-year-old Murray told reporters.
In the women's draw, defending champion Victoria Azarenka and Serena Williams, who will hoping to shake off injury doubts, will also play under a scorching sun as the opening two acts at Rod Laver Arena.
Azarenka will play Greece's Eleni Daniilidou before Williams faces Spaniard Garbine Muguruza.
Australia's Bernard Tomic, bearing his country's hopes after ninth seed Sam Stosur was knocked out of the women's tournament, has been given centre court billing for his match against Germany's Daniel Brands in the last match of the day session at Rod Laver Arena.
The much-vaunted 20-year-old will aim to set up a potential third-round match against Federer.
- Reuters and The Age