Canadian Frank Dancevic slammed Australian Open organisers for forcing players to compete in "inhumane" conditions after he collapsed on court as temperatures rose to 41C on Tuesday.
Dancevic, who collapsed during the second set of his first round match against France's Benoit Paire on the uncovered court six at Melbourne Park and passed out for a minute, said conditions were plainly dangerous for the players.
"I think it's inhumane, I don't think it's fair to anybody, to the players, to the fans, to the sport, when you see players pulling out of matches, passing out," he told reporters.
"I've played five set matches all my life and being out there for a set and a half and passing out with heat-stroke, it's not normal.
"Having players with so many problems and complaining to the tournament that it's too hot to play, until somebody dies, they're just keep going on with it and putting matches on in this heat.
"I personally don't think it's fair and I know a lot of players don't think it's fair."
The tournament's "extreme heat" contingency plan was put into force for women's matches on Tuesday, allowing an extra 10-minute break between the second and third sets.
Under a change to the rules for this year, however, the decision on whether to stop matches at the tournament is now at the discretion of tournament director Wayne McKewen.
Rather than use the raw Celsius readings to assess the heat, organisers prefer to use the Wet Bulb Global Temperature composite, which also gauges humidity and wind to identify the perceived conditions.
Organisers said temperatures peaked at 42.2C in the early evening on Tuesday and conditions had never reached the point where play would be stopped.
"We have to reach a minimum threshold and have a forecast that it will be sustained for a reasonable time," McKewen said in a statement.
"That didn't happen. While conditions were hot and uncomfortable, the relatively low level of humidity ensured play would continue."
Dancevic, who said he had felt dizzy from the middle of the second set, resumed after medical attention but unsurprisingly ending up losing 7-6 6-3 6-4.
"I was really close to stopping completely," he said. "I wasn't really running too much towards the end. I wasn't tired, I just felt my body temperature was too high."
A ball boy had earlier required medical attention after collapsing during Milos Raonic's 7-6(2) 6-1 4-6 6-2 victory over Daniel Gimeno-Traver on the equally exposed court eight.
China's Peng Shuai said the heat had caused her to cramp up and vomit and she had to be helped from the court after her 7-5 4-6 6-3 defeat to Japan's Kurumi Nara.
Former world number one Caroline Wozniacki reported that her water bottle had started to melt as she cantered to a 6-0 6-2 success against Lourdes Dominguez Lino.
Defending champion Victoria Azarenka described playing in the conditions as akin to "dancing in a frying pan".
The only bum note a resurgent Jelena Jankovic hit in her 6-1 6-2 victory against Misaki Doi was when she suffered a scorched posterior after sitting on a metal seat.
Many competitors, though, followed Roger Federer's line that, although conditions were tough, they were the same for both players.
"It's just a mental thing," the Swiss said, albeit before Dancevic collapsed. "If you've trained hard enough your entire life or the last few weeks and you believe you can do it and come through it, there's no reason.
"If you can't deal with it, you throw in the towel."
"I don't think it's much to do with the shape the players are in, some players are used to the heat, their bodies can genetically handle the heat, and others can't," Dancevic said.
"It's hazardous to be out there, it's dangerous. It's been an hour and a half after my match and I still can't pee."