MELBOURNE (AFP) - Serena and Venus Williams looked in ominous form as they powered through the first round of the Australian Open on Tuesday, but Russia's Elena Dementieva struggled against an unheralded opponent.
Serena overpowered China's Meng Yuan 6-3, 6-2 while older sister Venus downed Germany's Angelique Kerber 6-3, 6-3.
However Dementieva, who crushed Serena at last week's Sydney International, was forced to fight for two hours before finally seeing off German Kristina Barrois.
Dementieva said she feared her Australian Open dream was evaporating in the Melbourne Park heat before she ground out the 7-6 (7/4), 2-6, 6-1 win.
The in-form Russian won titles in Auckland and Sydney leading into the Open, but found herself struggling against Barrois' aggression.
Playing on the same court where she tumbled from the tournament's opening round in 2006, the 27-year-old feared history was set to repeat against the unseeded German.
"I was thinking 'Oh, no, it's going to happen again'," she said.
"I think she played really well. She had nothing to lose and was really going for the shot, making some winners and great serve. It was a really tough match to play.
"I'm just happy to survive."
There were no such problems for Serena and Venus, who could well meet in the semi-finals.
Serena is looking for her 10th major crown and her fourth in Melbourne, following wins here in 2003, 2005 and 2007.
Forgoing her usual flashy outfits for a nondescript dark blue number, the American powered past Meng in just 75 minutes.
"I think I hit some pretty solid shots, sometimes I even went for some shots just to try something different," she said, downplaying the effect of the heat.
"There wasn't so much humidity out there, the dry heat is actually better than the humidity. But it was definitely extreme conditions."
Venus, who has yet to lift the Melbourne title, was untroubled by Kerber.
"I'm feeling the best that I can and I'm glad to be in the second round," she said.
Standing in the way of a possible Williams semi-final are Dementieva, in the same part of the draw as Venus, and Svetlana Kuznetsova, who battled for 100 minutes before downing Australia's Anastasia Rodionova.
The eighth seeded Russian, in Serena's quarter of the draw, beat the Australian 6-2, 3-6, 6-3.
Also moving through were 13th seeded Belaursian Victoria Azarenka, an easy 6-2, 6-1 winner over Petra Kvitova and China's unseeded Peng Shuai, who sent Italian 28th seed Francesca Schiavone packing.
Wimbledon semi-finalist Zheng Jie beat France's Camille Pin, while former Australian Open champion Amelie Mauresmo eased to a 6-4, 6-3 win over Olga Govortsova.
The biggest casualty so far came when ninth seed Agnieszka Radwanska tumbled out at the hands of Ukraine's Kateryna Bondarenka.
The Pole, a quarter-finalist here last year, lost 7-6 (9/7), 4-6, 6-1.