Fifteenth seed Sabine Lisicki has lost her second round singles game against Romania's Monica Niculescu. Top seed Serena Williams cruised through in the searing heat, as did Germans Mona Barthel and Florian Meyer.
Grass court specialist Sabine Lisicki, a Wimbledon finalist last year, could not justify her seeded status for the first Grand Slam of the calendar year in Melbourne. The German lost in three sets (6-2, 2-6, 2-6) on Wednesday to Monica Niculescu.
"I did everything right for about one-and-a-half sets, but then the heat got to me," Lisicki said after another scorching day with temperatures hitting 40 degrees Celsius (104 Fahrenheit) in the shade. "There comes a point when it's just too hot to play professional sports."
The 24-year-old at least managed to play out her defeat, unlike 10 other players who have withdrawn from the tournament so far - a record number since 1968 at this early stage of a Grand Slam. Lisicki's game became littered with unforced errors in the latter stages, also affecting the big-hitter's all-important serve. "That can happen when the heat gets the better of the body," she said.
The heat wave gripping the coastal city is expected to endure until Friday. Fellow German Mona Barthel, a year Lisicki's junior, was able to overcome Thai player Luksika Kumkhum 4-6, 6-3, 6-4.
"I drank as much as I possibly could. I'm really happy to have made the third round," Barthel said afterwards.
Last year's finalist Li Na of China beat rising Swiss teen star Belinda Bencic 6-0, 7-6, with Bencic putting up stern resistance in the second after the first set blowout.
Top women's seed Serena Williams, five times a winner in Melbourne, waltzed past Vesna Dolonc of Serbia, winning 6-1, 6-2 in barely an hour's play. The draw was somewhat kind to the 32-year-old, who paced herself against her opponent, ranked 104 in the world.
German ninth seed Angelique Kerber made short work of Alla Kudryavtseva (6-4, 6-2) to advance to the third round.
In the men's draw, German Florian Mayer took three times as long as Williams to clinch his third-round berth on Wednesday. Unseeded Mayer surprisingly overcame Mikhal Youzhny of Russia, seeded 14th, in five sets: 6-4, 3-6, 6-3, 3-6, 6-3.
Qualifier Michael Berrer is the only other remaining German hopeful left in the competition, he faces Spaniard Feliciano Lopez on Thursday.
Second seed, defending champion and four-time Australian Open champion Novak Djokovic, with new manager Boris Becker in tow, also proceeded to round three on Wednesday. Djokovic dispatched Leonardo Mayer of Argentina 6-0, 6-4, 6-4. The Serb won his first ever Grand Slam on the Australian hard courts back in 2008.
Spain's second-best player, David Ferrer, overcame a sluggish start to beat France's Adrian Mannarino in four sets: 7-6 (2), 5-7, 6-0, 6-3. Ferrer is considered one of Djokovic's toughest potential opponents on their side of the bracket.
msh/mz (dpa, Reuters, SID)