Rafael Nadal, Roger Federer and Andy Murray all safely made it through to the second round of the Australian Open as tempatures soared, causing players to faint and vomit all day.
Murray, who overpowered Japan's Go Soeda 6-1, 6-1, 6-3, warned organisers were risking a tragedy as he queried whether it was safe to play in temperatures which touched 42.2 Celsius (108 Fahrenheit).
"Whether it's safe or not, I don't know. You've just got to be very careful these days," said the world number four after his first-round win. "There's been some issues in other sports with, you know, players having heart attacks. I don't know exactly why that is. Or collapsing."
On one of the hottest days the tournament has ever seen, untoward incidents littered the day and overshadowed the conclusion of round one at Melbourne Park.
Federer, watched by new coach Stefan Edberg, was regal in his 6-4, 6-4, 6-2 win over Australia's James Duckworth, while in the comparative cool of the evening session, Nadal was given easy passage when mercurial home hope Bernard Tomic retired with a thigh injury when one set down.
"I felt really sorry for Bernard. I was in that situation a few years ago and I know how tough is to take that decision," said Nadal, who retired himself during the 2010 quarter-finals. "But if you feel bad, there is no reason why you have to continue. You're risking the next tournaments for nothing."
And it was the severe heat that dominated discussion, after Canada's Frank Dancevic felt dizzy and then blacked out during his loss to Benoit Paire.
"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 complained. "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."
Meanwhile, a ball boy collapsed during Milos Raonic's win over Daniel Gimeno-Travers, and China's Peng Shuai cramped up and vomited before losing to Japan's Kumuri Nara.
"I had no energy, I couldn't run, I couldn't serve," she said, blaming the heat for her defeat. "So it's impossible to play tennis like this."
Japan's Kei Nishikori came through a thrilling five-setter with Marinko Matosevic, but Australian veteran Lleyton Hewitt was sent crashing despite going the distance with Italy's Andreas Seppi.
Former finalist Jo-Wilfried Tsonga went through smoothly against Filippo Volandri and Juan Martin del Potro won in four sets against America's Rhyne Williams.
Perhaps the toughest encounter of the day was between France’s Gilles Simon who eventually overcame Germany’s Daniel Brands 6-7 (7-4), 6-4, 3-6, 6-3, 16-14 to make it through to the second round.
In the women's draw, defending champion Victoria Azarenka beat Johanna Larsson and former world number one Caroline Wozniacki ousted Lourdes Dominguez Lino for the loss of just two games.
"Sometimes it can be tricky, you know, to find your range, as it was today a little bit," said number two seed Azarenka, admitting she still needed to work on aspects of her game. "I'll just try to keep the things that have been working before, what I was working on in Brisbane and my off-season and just try to reproduce it more and more and be disciplined with that."
Maria Sharapova, still using ice vests in temperatures over 30 Celsius after 11:00 pm, beat Bethanie Mattek-Sands 6-3, 6-4.
"After (missing) my last Grand Slam in New York I have been so looking forward to this one and I was really happy to start," said Sharapova. "She was a tough opponent and I'm just happy to get through the first one.”
Fifth seed Agnieszka Radwanska, who has made the quarter-finals here for the past three years, needed three sets to stay alive but it was easier for 2008 semi-finalist Jelena Jankovic who went through in two.
Others safely into the second round included Spain's 16th seed Carla Suarez Navarro, French 25th seed Alize Cornet, courtesy of an early retirement, and Slovakia's Dominika Cibulkova.
Cibulkova beat veteran Italian Francesca Schiavone, who was playing her 54th consecutive Grand Slam. Only one woman in the Open era has bettered that total — Japan's Ai Sugiyama, who played 62 in a row.
