Andy Murray and Serena Williams took the easy route at the Australian Open on Tuesday, breezing into the second round in furnace-like conditions.
As temperatures soared past 40 Celsius (104 Fahrenheit), fourth seed Murray barely broke a sweat against Romanian Davis Cup captain Andrei Pavel who retired with a back injury when the Scot was leading 6-2, 3-1.
The second-seeded Williams was equally comfortable in her 6-3, 6-2 mauling of China's Meng Yuan, not needing the ice vests players can wear between games in such sizzling heat.
While she cruised, Russian fourth seed Elena Dementieva survived a gruelling test before grinding down Germany's Kristina Barrois in three sets, while Polish ninth seed Agnieszka Radwanska became the biggest casualty so far.
Murray is now undefeated in six matches this season as he goes in search of Britain's first Grand Slam title since 1936.
"Obviously you don't want to finish a match like that. Andrei's been having problems with his back for a year," said the world number four.
"It's unfortunate I had to stop but I felt like I was hitting the ball well. I guess if you want to do well in the tournament, it's good to conserve some energy. Hopefully that was a good thing."
The Scot, who was coasting through the match after breaking twice to take the opening set in 31 minutes, is the form player of recent months and is seen as a real chance to win his maiden Grand Slam title in Melbourne.
The experienced Williams is looking for her 10th major crown and her fourth in Melbourne.
Only a few select women, including Steffi Graf, Martina Navratilova and Chris Evert, have won more major titles than the formidable 27-year-old.
Forgoing her usual flashy outfits for a nondescript dark blue number, the American powered past Meng in just 75 minutes.
"It was pretty hot out there," she said. "But I'm just happy to be here. This is a special place for me."
Her sister Venus, who has yet to lift the Melbourne title, is on court later on Tuesday against Germany's Angelique Kerber.
Dementieva is widely regarded as a dark horse for the championship after already winning two titles this year.
But the Beijing Olympic gold medallist was pushed to the limit in the 7-6 (7/4), 2-6, 6-1 win, emerging victorious after more than two hours to take her recent unbeaten run to 11 matches.
"I'm just happy to survive," she said. "I've played a lot of tennis recently and it was very hot out there."
Other players to progress included 13th seed Victoria Azarenka of Belarus, while China's unseeded Peng Shuai sent Italian 28th seed Francesca Schiavone packing.
On the men's side, Austria's Jurgen Melzer ended the dreams of rising Japanese star Kei Nishikori in straight sets while Uzbekistan's Denis Istomin beat America's Vincent Spadea.
World number one and top seed Rafael Nadal plays later on Tuesday against Belgium's Christophe Rochus.