Despite warning all week that extreme temperatures would hit Melbourne on Thursday, few were prepared when temperatures did indeed soar to 106 degrees.
Yet the retractable roof over Rod Laver Arena remained open, a decision driven by the relatively low humidity.
That may have satisfied the extreme temperature index that drives these roofing decisions, but it didn't offer much solace to the players and fans. Seats were empty for much of the day, as spectators sought shade rather than tennis.
Players jostled for ice baths in the locker room. As the day went on, the roof over Laver never moved, causing some to question the decision.
Victoria Azarenka was first up on Rod Laver Arena at 11 a.m. and was conscious of getting off the court quickly, which she did, dropping just one game in a 55-minute romp over Eleni Daniilidou.
"It was pretty hot," Azarenka said. "That's why I was trying to play fast. The first match I got a little bit sunburned. You don't want to make that mistake again."
Andy Murray was just relieved he didn't have the humidity to deal with.
"When the sun came out, it was extremely hot," Murray said. "When it wasn't, it was fine. There was no humidity. They said it was like eight percent humidity. When you get the combination of the heat and the humidity is when it's normally at its worst. I've played in worse conditions, but it's still very hot."
Many of the top players spend their offseasons in Florida or the Middle East. So when they say it's hot, it's hot.
No one had it tougher than Blaz Kavcic. The Slovenian was locked in a near-five-hour duel with Australian wild card James Duckworth on Court 3. As the match went into extra innings, 6-6 in the fifth set, Duckworth was clearly cramping. Kavcic slogged his way through points. Kavcic eventually won 3-6, 6-3, 6-4, 6-7, 10-8 in four hours and 52 minutes, the longest match of the tournament so far. After, Kavcic went into a full body cramp and needed a muscle relaxant to ease the pain.
This is what playing in 106 degrees for almost five hours looks like.