Martina Hingis booked her place in the fourth round of the Australian Open with a 6-4 6-1 win over Iveta Benesova of the Czech Republic.
Hingis has dropped only 10 games in her three matches so far
The three-times former champion was briefly rattled in the first set when her 22-year-old opponent led 3-1.
But at 4-4, Benesova, who beat Mary Pierce on Thursday, produced an awful game featuring three double faults and Hingis needed no second invitation.
The former world number one now faces home favourite Samantha Stosur.
Stosur, the world number 98, beat Austrian Sybille Brammer 7-5 4-6 6-3.
Hingis, who has dropped only 10 games en route to the fourth round, insisted there was still work to be done on her game.
"I was down 3-1 today, down a break, but thankfully, I broke right back. That felt really good," she said.
"I don't think I played my best tennis today but as long as you win it's always good. But there is always room to improve for the next match."
World number two Kim Clijsters shrugged off the effects of hip and back injuries to ease into the fourth round.
The Belgian easily disposed of the challenge of Italy's Roberta Vinci 6-1 6-2 in only 44 minutes.
"It's the first match where I've played really well and my body was actually feeling a lot better than the last two matches," she said.
Clijsters will meet Italy's Francesca Schiavone in the fourth round.
Third seed Amelie Mauresmo faces an intriguing meeting with 16-year-old rising star Nicole Vaidisova after both advanced to the fourth round.
Mauresmo booked her place in the last 16 when Michaella Krajicek retired with heat stress after losing the first set 6-2.
"It's always strange to finish a match this way," said Mauresmo, winner of the WTA Championships in November.
Vaidisova, the Czech 16th seed, saw off the challenge of Italy's Flavia Pennetta 6-4 6-2.
Anastasia Myskina made it five Russians in the last 16 with a 6-3 6-1 win over Sofia Arvidsson.
The former French Open champion struggled throughout in the windy and hot conditions, making 33 errors, but she also hit 20 more winners than Arvidsson.
"I don't really know how to use the wind when I play, so I was fighting for every point," said Myskina, who now faces seventh seed Patty Schynder.
Schnyder recorded a routine 6-2 6-3 win over the unseeded Aiko Nakamura of Japan.