Defending champion Victoria Azarenka and 15-time major titlist Serena Williams were both easy second-round winners on Thursday at the Australian Open.
Belarus' top-seeded Azarenka converted on 5-of-8 break chances and took advantage of five double faults by Greek Eleni Daniilidou to cruise to a 6-1, 6-0 victory at Rod Laver Arena.
Daniilidou was eliminated in the second round at this tournament for the second straight year and has not reached the third round since 2004.
The third-seeded American Williams, meanwhile, continued her quest for her sixth Aussie crown with a 6-2, 6-0 pasting of Garbine Muguruza.
The reigning U.S. Open and Wimbledon winner powered past the Spaniard with 10 aces and just one double fault.
Former world No. 1 Carolina Wozniacki was another straight-set winner on Thursday with a 6-1, 6-4 decision over Croatia's Donna Vekic.
The 10th-seeded Dane converted on 5-of-7 break opportunities and capitalized on 32 unforced errors by her opponent to advance.
Other seeded players to move on to the third round included 14th-seeded Russian Maria Kirilenko and 16th-seeded Italian Roberta Vinci, as Kirilenko downed China's Peng Shuai 7-5, 6-2 and Vinci took a 6-3, 6-2 win over Uzbekistan's Akgul Amanmuradova.
Vinci has not advanced past the third round in seven previous appearances at this event, while Kirilenko was an Australian Open semifinalist in 2010.
20th-seeded Yanina Wickmayer of Germany also advanced with a 7-6 (10-8), 7-5 victory over Slovakia's Jana Cepelova in just over two hours.
There were a couple of upsets on Day 4 as 21st-seeded American Varvara Lepchenko committed six double faults and converted just 1-of-8 break chances against Russia's Elena Vesnina en route to a 6-4, 6-2 defeat, and Russian Svetlana Kuznetsova ripped sevens aces during a 6-2, 6-1 win over Chinese Taipei's Su-Wei Hsieh, the tournament's 26th seed.
Vesnina is coming off her first-ever WTA title last week in Hobart.
In the day's unseeded matchups, Ayumi Morita of Japan earned a 6-2, 6-0 decision over Germany's Annika Beck, America's Jamie Hampton rolled past Thailand's Luksika Kumkhum 6-1, 6-2, Ukraine's Lesia Tsurenko defeated Russia's Daria Gavrilova 7-5, 6-3, Japan's Kimiko Date-Krumm took a 6-2, 7-5 victory over Israel's Shahar Peer and Carla Suarez Navarro of Spain outlasted Kazakhstan's Yulia Putintseva 1-6, 7-6 (7-5), 6-2.