MELBOURNE, Australia -- Serena Williams wore a fitted pink blazer into her second-round match at the Australian Open, giving the impression she wasn't feeling the heat.
And after her 6-1, 6-2 win over Vesna Dolonc on Wednesday, the second consecutive scorching day at the season's first major, Williams said she could remember hotter matches.
By improving her career mark to 60-8 at Melbourne Park, she equaled Margaret Court's record 60 match wins at the Australian Open in the Open era.
On day three at Melbourne Park, the center court at Rod Laver Arena was -- at least according to the two fans holding up a sign -- "Serena's Arena."
The heat topped 40 Celsius (104F) during the 63-minute match, and peaked at just under 42 C (108 F) later during Novak Djokovic's 6-0, 6-4, 6-4 win over Leonardo Mayer. Second-seeded Djokovic, aiming to be the first man in the Open era to win four consecutive Australian Open titles, didn't face a break point.
Williams fended off the only break point she faced with an ace, one of her 10 in the match. She hit 24 winners, sticking to the ideal strategy of keeping the points short on a hot day and extended her winning streak to 24 matches.
She said didn't even go outside Tuesday because conditions "were a little bit extreme," adding that the prospect of the scorching temperatures had even interrupted her sleep.
"I kept waking up in the middle of the night last night just paranoid. I just wanted to stay hydrated," she said. "The last thing I want to do is to cramp in this weather. It can happen so easy."
Williams next meets No. 31-seeded Daniela Hantuchova, who was on court for 3 hours, 13 minutes in her 6-3, 3-6, 12-10 win over Karolina Pliskova.
Temperatures topped 42 Celsius (108F) on Tuesday, and there were a total of nine retirements in the first round, equaling a Grand Slam record. It wasn't quite as stifling Wednesday, but the forecast is for the heat wave to continue until Friday.
Li Na, the 2011 French Open champion and a two-time finalist at Melbourne Park, had a 6-0, 7-6 (5) win over 16-year-old Belinda Bencic and will next play No. 26 Lucie Safarova in the third round.
No. 9 Angelique Kerber advanced and will next meet American Alison Riske, who trounced Yanina Wickmayer 6-1, 6-1. Australian wild-card entry Casey Dellacqua upset No. 18 Kirsten Flipkens 6-3, 6-0.
No. 17 Sam Stosur is through to the third round of her home Grand Slam for the first time in three years after a 6-2, 6-0 win over Tsvetana Pironkova. No. 30 Eugenie Bouchard of Canada beat Virginie Razzano 6-2, 7-6 (10) and Zheng Jie defeated American Madison Keys 7-6 (5), 1-6, 7-5.
The tournament's heat rule went into effect in the first match on Margaret Court Arena, giving No. 15-seeded Sabine Lisicki and Monica Niculescu a 10-minute break after the second set. Niculescu won 2-6, 6-2, 6-2 and will next play No. 22 Ekaterina Makarova, who followed up her win over Venus Williams with a 6-2, 7-5 victory over American Irina Falconi.
Djokovic had a brief scare while serving at 3-0 in the first set when he turned over on his left ankle, tumbling to the court. It didn't warrant medical attention during the next break in play and he took the opening set in just 22 minutes, allowing Mayer to win just eight points.
"It was just I slipped a little bit," Djokovic said. "It was an instant discomfort, but it was OK after."
No. 3 David Ferrer beat Adrian Mannarino of France 7-6 (2), 5-7, 6-0, 6-3 to advance along with No. 7 Tomas Berdych and No. 9 Richard Gasquet, No. 17 Tommy Robredo, No. 20 Jerzy Janowicz and No. 29 Jeremy Chardy.
Florian Mayer beat No. 14 Mikhail Youzhny, Uzbekistan's Denis Istomin defeated No. 30 Dmitry Tursunov and Bosnian qualifier Damir Dzumhur advanced when No. 32-seeded Ivan Dodig retired with cramps while leading in the fourth set.
Sam Querrey fired 19 aces, saying he had "one of the best service days of my life" in a 6-2, 6-3, 6-4 upset win over No. 23 Ernests Gulbis.