Andy Murray's first win at Rod Laver Arena lasted only 45 minutes. Lucky him.
The second-seeded Williams, who has an alternate year pattern of titles here since 2003, had a 6-3, 6-2 win over China's Yuan Meng in 75 minutes in the following match on center court.
"Ooh! It's a little hot out here," Williams said. "It was definitely extreme conditions."
Murray only needed to play 12 games to advance — Andrei Pavel retired with a back problem down 6-2, 3-1. When they walked off, the temperature was hovering at 99.
In addition to the heat, the early afternoon sun was nearly blinding at one end of the court.
Williams let several service tosses drop during one game before shortening her motion, costing her some speed.
When a passing cloud brought brief relief, a fan shouted, "Close the roof!" A swirling, gusty wind added unpredictability, and a flurry of moths annoyed the players and sent staffers scurrying to sweep them off the court during changeovers.
Williams, who won the first of her nine majors in Melbourne, attributed her success here with the timing of the event.
"Maybe a new year, wanting to start out the year well," she said. "Also, it seems to not matter in what condition I come in here, I'm able to at least play a solid game."
Photographers at courtside draped their heads, bodies and cameras in wet towels. Spectators fanned themselves with paper and official programs.
Oracene Price, mother and coach of Serena and Venus Williams, sat in the bleachers under an oversized straw hat. She had another first-round match to watch later Tuesday.
The temperature dropped to 79 degrees by the time sixth-seeded Venus beat Germany's Angelique Kerber on the second showcourt.
Venus Williams, the reigning Wimbledon champion, rallied from 3-1 down in the second set to win five straight games and the match.
Williams, in a bright yellow dress, rushed to a 5-0 lead in the first set. But Kerber's go-for-broke style started working. She broke Williams, then fended off three set points, before Williams finished off the set with her fifth ace.
Kerber broke again to pull ahead 3-1. It was the last game she won as Williams started catching the lines again.
Olympic gold medalist Elena Dementieva beat Germany's Kristina Barrois 7-6 (4), 2-6, 6-1. Also advancing were No. 13 Victoria Azarenka of Belarus, 2006 champion Amelie Mauresmo of France and No. 22 Zheng Jie of China.
No. 9 Agnieszka Radwanska of Poland went down to Ukraine's Kateryna Bondarenko 7-6 (7), 4-6, 6-1. She was the highest of the seeded players to fall so far.
On the men's side, No. 5 Jo-Wilfried Tsonga beat Argentina's Juan Monaco 6-4, 6-4, 6-0, No. 6 Gilles Simon beat Spain's Pablo Andujar 6-4, 6-1, 6-1. Their fellow Frenchman Richard Gasquet, seeded 24th, advanced in four sets over Diego Junqueira.
No. 13 Fernando Gonzalez of Chile ended local hope Lleyton Hewitt's 13th Australian Open in the first round. Gonzalez, seeded 13th and runner-up here to Roger Federer in 2007, won 5-7, 6-2, 6-2, 3-6, 6-3.
Hewitt, a former U.S. Open and Wimbledon champion, lost the final at his home major in 2005 to Marat Safin.
No. 17 Nicolas Almagro of Spain, No. 25 Ivo Karlovic of Croatia, and No. 31 Jurgen Melzer of Austria also got through. Melzer overpowered 19-year-old Japanese player Kei Nishikori 7-5, 6-2, 6-1.
Tsonga had upset wins over then No. 9 Murray in the first round and Rafael Nadal in the semifinals here last year before losing the final to Novak Djokovic.
This year, Murray is carrying the hopes of a British public looking for its first male Grand Slam champion since 1936.
The 21-year-old Scot, who lost last year's U.S. Open final to Roger Federer, went back out to practice after the sudden finish to his first match.
"It's the first time I've ever won a match here," he said. "You don't want to win a match like that."
Murray was installed as the favorite or joint favorite for the tournament by British bookmakers after beating Federer three times since losing the U.S. Open final — his best run at a major to date.
"I'm aiming to go one better here and I need all the support I can get," he said, noting the number of Scottish flags unfurled around the stadium. "It's nice. Hopefully they'll keep coming throughout the tournament."
Murray defended his Qatar Open title before coming to Melbourne but said it was still difficult getting used to the Australian summer.
"Even when you sit down at the change of ends, you're expecting to sort of go and chill out a little bit in the shade and it's roasting even when you're just sitting there," he said. "That was tough. If you have a long point, you can feel your feet burning a little bit."
Nadal, who replaced Federer atop the rankings, had a night match Tuesday against Christophe Rochus of Belgium, about the same time No. 9 James Blake is due to play Canada's Frank Dancevic.