Victoria Azarenka remained undefeated this season after eliminating former champion Amelie Mauresmo 6-4, 6-2 on Saturday to move into the second week of the Australian Open.
The 13th seed from Belarus, polished her 2009 mark to 8-0 after winning the Sydney title in a fast start to this season.
The 19-year-old who lives in Arizona will face off in the fourth round against three-time champion Serena Williams, who shoved aside mental images of the male streaker who interrupted her on Friday doubles with sister Venus.
Williams, seeded second and champion at Melbourne Park in 2003, 2005 and 2007, dispatched China's Peng Shuai 6-1, 6-4.
The American said she was more amused than shocked when a spectator wearing just a t-shirt danced across the doubles court 24 hours earlier. The streaker lasted for less than a minute before being taken off by security officials.
"This is crazy, doesn't really happen too much," said Williams. "Then I just thought, my eyes, my innocent eyes ..."
Williams added: "I saw him jump over and then I noticed he didn't have underwear on. I thought, 'I must be seeing things.' Then he disappeared."
"Then he ran out on the court. I was like, 'I hope he doesn't come, he's too close.'"
Italian 12th seed Flavia Pennetta missed a chance to advance towards a top ten ranking as she lost to Spain's Anabel Medina Garrigues 6-4, 6-1
There was continued momentum for unfancied Spaniard Carla Suarez Navarro, winner over Venus Williams a round earlier, with the 20-year-old advancing over compatriot Maria Jose Martinez Sanchez 6-1, 6-4.
Zheng Jie got a victory for China, beating Kateryna Bondarenko of Ukraine 6-2, 6-2.
Men's 12th seed Gael Monfils reached the second week in Melbourne for the first time in his career with a knockout of Spain's Nicolas Almagro 6-4, 6-3, 7-5
Roland Garros semi-finalist Monfils, coached by Australian Roger Rasheed, held his unforced error count to 24, with Almagro committing nearly twice as many.