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The players are out in the already ridiculously hot temperatures on court two.
Kyle Edmund hands a bag packed full of bottles of water to a ball boy. I assume that bag will be heading straight for the freezer.
The warm-ups are under way.
Image source, Getty ImagesKyle Edmund's opponent today is a 25-year-old, big-hitting Georgian ranked at 61 in the world.
Nikoloz Basilashvili's two victories so far in this tournament have been his first at the Australian Open and he is bidding to reach the last 16 of a Grand Slam for the first time.
His dad was a dancer in Georgia's National Ballet and he is aiming to become just the fourth player from his country to reach the fourth round of a major.
I'll be mightily impressed if you can name the others...
David Law
Radio 5 live sports extra commentator at Melbourne Park
There are question marks over whether they should play in this. If the heat rule wasn't going to be employed on a day like yesterday when will it be invoked? You had players leaning on racquets in the second set of matches. Super-fit athletes struggling to carry on - it wasn't a great spectacle.
BBC Radio 5 live sports extra
A quick reminder that you can listen to live coverage of tonight's tennis from Melbourne from our team down under.
BBC Radio 5 live sports extra will bring you commentary of Edmund v Basilashvili and are already on air with build-up.
Tune in by clicking play at the top of this page.
For any doubting the fortunes of British men's tennis after Andy Murray, this week Kyle Edmund has continued to prove there should still be plenty to shout about.
The 23-year-old claimed the best win of his career in round one by beating world number 12 Kevin Anderson in five sets before cruising past the dangerous Denis Istomin in round two.
Today he goes into his third round match as the favourite against a player ranked below him at 61 in the world.
As the last British player remaining in the singles draws, all eyes are on him.
Image source, Getty Images
Piers Newbery
BBC Sport at Melbourne Park
Heat. It's all anyone is taking about here. As the passing Mark Petchey just pointed out, the temperature is no different to many previous years, so the debate is really whether you play tennis in 40C or not.
The tournament's Extreme Heat Policy was last enforced in 2014 when the temperature hit 41.7C, and that could well be matched today. But it is not just down to temperature, it's a combination of factors that also include humidity, wind speed, sun angle etc.
The feeling right now is that it's hot, but not humid, and that play will go on. Good luck everyone!
Image source, BBC Sport
Image source, EPAHello there!
Yesterday some wilted in the Melbourne heat and the bad news is today on day five the mercury is set to rise even further with temperatures of over 40C forecast.
On a sweltering day four Johanna Konta's campaign ended and that means Kyle Edmund is in the spotlight today as the last Briton standing in the 2018 Australian Open singles.
Image source, EPAMurray - out before it begun.
Konta - out.
Watson - out.
This is Kyle Edmund's day in the scorching Melbourne sun.
Image source, Getty Images