Andy Murray and Victoria Azarenka breezed into the third round in Melbourne, while Serena Williams' progress proved more painful after hitting herself in the face with a racquet.
Australian Open: Murray and Azarenka keep their cool despite soaring temperatures
Andy Murray kept his cool in Melbourne's soaring temperatures to power through to the Australian Open third round in straight sets against Joao Sousa.
The reigning US Open champion conceded just eight games in putting away 100th-ranked Portguese Joao Sousa, 6-2, 6-2, 6-4 in 1hr 41 min on Hisense Arena.
With temperatures reaching 39 degrees, the Scot was too hot to handle, breaking Sousa's service five times without facing a break point.
Murray, a twice runner-up at the Australian Open, will next play Lithuanian qualifier Ricardas Berankis, who was his practice partner when he won the lead-up Brisbane International two weeks ago.
"It's tough to get used to these conditions and it was extremely tough out there, and it was good to get it done in three sets."
Roger Federer cruised into the third round after a 6-3 6-4 6-4 win over Nikolay Davydenko.
Federer, wearing a pair of pink and black trainers, recorded a break early in each set, leaving the veteran Russian on the back foot throughout their two hours.
The result sets up a clash with outspoken rival Bernard Tomic, who narrowly defeated Daniel Brands.
The 20-year-old Australian secured a 6-7 (4/7), 7-5, 7-6 (7/3), 7-6 (10/8) win in 2hr 55min over the German qualifier to reach the third round and continue his unbeaten start to the year after claiming his first tour title at the Sydney International.
"Unexpectedly, he played really well," Tomic said of Brands. "In the end I was surprised how well he played. A set down, I didn't feel too good but I managed to turn it around."
Victoria Azarenka, the defending champion, said she was "in the zone" with her game exactly where she wants it as she cruised into the third round.
The world number one Belarusian lost just one game in a 6-1, 6-0 thrashing of Greek Eleni Daniilidou and will next play American Jamie Hampton.
"I felt really good, I enjoyed a lot the way I was focused," she said.
"I definitely stepped it up from my first match, and I was in the zone trying to execute all of my shots. I was trying to make everything happen, and that's what I'm happy about."
Serena Williams brushed aside any injury worries to sweep into the Australian Open third round on Thursday with a straight sets defeat of Garbine Muguruza.
But the third seed finished the match with a split lip after accidentally hitting herself in the face with her racquet while going for a lop.
"I think it happens to everyone, but I have never busted it wide open like that. So, yeah, I was like, 'Oh, no, I can't have a tooth fall out.' That would be horrible.
"I don't know why my racquet was even in my face," she added. "I mean, it's like I have been playing tennis far too long to hit myself. I'm like, come on Serena, pull yourself together."
The 15-time Grand Slam winner, gunning for a sixth Australian title, rolled her ankle on Tuesday but was moving freely in the 6-2, 6-0 defeat of the Spaniard.
She next plays Japan's Ayumi Morita, who beat German Annika Beck, and if the draw goes to plan is scheduled to meet world number one Victoria Azarenka in the semi-finals.
Jo-Wilfried Tsonga said he was looking to play more aggressively after fending off Japan's Go Soeda to make the third round.
The 2008 runner-up was made to toil hard in the heat for his 6-3 7-6 (7/1) 6-3 win over 73rd-ranked Soeda.
It was seventh-seeded Tsonga's second victory in straight sets in the tournament and puts him in the last 32 where he will face an unseeded opponent, either James Duckworth or Blaz Kavcic.
"It was hot today and it wasn't easy because the ball was flying a lot because of the heat," he said.
It was plain sailing in the final set for the Frenchman with a break in the sixth game, and he finished the match with 17 aces and 44 winners.
Japanese veteran Kimiko Date-Krumm racked up another record by becoming the oldest player to make a Grand Slam third round since Renee Richards in 1979.
The 42-year-old defeated Shahar Peer 6-2, 7-5 with only Richards, aged 45, getting as far at such at an age. If Date-Krumm wins her next match she will be the oldest ever to make the fourth round of a major tournament.
"In the last 10 years it's more powerful, more speedy," she said. "Every time when I go to the gym, everybody is there, even before the match, after the match, everybody there. They're doing so much exercise.
"That's why women's tennis is changing compared to 10 years ago, 20 years ago. It's more powerful."
Date-Krumm next plays either 17th-seeded Czech Lucie Safarova or Serb Bojana Jovanovski.
Gael Monfils survived an attack of the jitters to beat Yen-Hsun Lu of Taiwan 7-6 4-6 0-6 6-1 8-6 in the second round of the Australian Open on Thursday.
Monfils, unseeded as he makes his way back from a long injury absence, double-faulted on four successive match points before finally clinching victory in just under four hours.
"It was a bit crazy," Monfils said afterwards. "It was like, 'I need to hit an ace because I know it's going to be a double-fault for sure. It was weird."I think I got a bit lucky in the end."
Follow us @SprtNationalUAE