Serena Williams is still on track in her bid to win a record 23rd Grand Slam title.
The six-time Australian Open winner beat fellow American Nicole Gibbs 6-1, 6-3 in the third round on Saturday, when she didn't face a break point until she was serving for the match.
Dropping serve in that game was her only lapse in a match that then extended just beyond the hour - to 63 minutes to be precise. That made it one minute and one game longer than her only other match against Gibbs.
Williams started the tournament with difficult assignments in the first two rounds, but also got through those - against Belinda Bencic, with a career-high ranking of 7, and Lucie Safarova, a French Open finalist in 2015 - without dropping a set.
She has set the tone for the tournament. Williams will next play No. 16 Barbora Strycova, who beat No. 21 Caroline Garcia 6-2, 7-5.
Ekaterina Makarova led by a set and 4-0 but needed three sets and almost three hours to finally beat WTA Finals champion Dominika Cibulkova 6-2, 6-7 (3), 6-3.
"An amazing fight," Makarova said of her first win over sixth-seeded Cibulkova, the 2014 finalist at Melbourne Park. "I got, to be honest, a bit tight at 4-0 in the second set. But I'm still here. I love this Grand Slam."
In a momentum-swing match featuring some long streaks of games and 11 service breaks, Makarova got the decisive break in the eighth game of the deciding set and closed it next.
Makarova will play either 2016 semifinalist Johanna Konta, who beat her in the fourth round here last year, or former No. 1-ranked Caroline Wozniacki.
Mirjana Lucic-Baroni continued her unlikely run with a 3-6, 6-2, 6-3 win over Maria Sakkari, and so did American qualifier Jennifer Brady.
Before this week, the 34-year-old Lucic-Baroni hadn't won a match at Melbourne Park since her debut at the Australian Open in 1998. The 19-year gap in between match wins at a Grand Slam tournament broke the record set by Kimiko Date-Krumm, who went 17 years between match wins at Wimbledon.
Lucic-Baroni reached the semifinals of Wimbledon in 1999 as a 17-year-old and captured the Australian Open doubles title a year before that with Martina Hingis.
She next plays Brady, ranked No. 116, who had never played in the main draw of a major before she qualified for this week.
The 21-year-old American had a 7-6 (4), 6-2 win over 14th-seeded Elena Vesnina on Show Court 2, and is making the most of the occasion.
By saving five match points before rallying to beat Heather Watson in the second round, Brady effectively doubled her number of career wins.
On the men's side, No. 8 Dominic Thiem beat Benoit Paire 6-1, 4-6, 6-4, 6-4 to set up a fourth-round match against No. 11 David Goffin, who ended Ivo Karlovic's run 6-3, 6-2, 6-4.
The 37-year-old Karlovic's win in the first round set an endurance record - the 84 games in the win over Horacio Zeballos, which ended 22-20 in the fifth, was an Open-era mark for the tournament.