All of the top 10 women's singles seeds have reached the Australian Open third round for the first time since 2007.

Fifth seed Elina Svitolina completed the set when she beat American Lauren Davis 6-2 7-6 (8-6) in a match that finished at 00:45 local time.

The Ukrainian, searching for her first Grand Slam title, will play Spanish two-time major champion Garbine Muguruza next.

Karolina Pliskova and Belinda Bencic were among the winners on day four.

Eighth seed Serena Williams won the title in 2007 when she was unseeded.

She will play Wang Qiang in the third round on Friday, while defending champion Naomi Osaka takes on Coco Gauff in a rematch of their emotional US Open meeting in September.

Play was delayed on the outside courts on Thursday because of the dust and mud that came down during a rainstorm in Melbourne on Wednesday night.

On Margaret Court Arena, Swiss Belinda Bencic overcame Latvia's Jelena Ostapenko in a fluctuating match to the reach the third round.

The sixth seed, 22, lost four games in a row in both sets but still managed to win 7-5 7-5 against the 2017 French Open champion.

Muguruza progressed with a 6-3 3-6 6-3 victory over Australian Ajla Tomljanovic on Rod Laver Arena.

Czech second seed Karolina Pliskova had a straightforward 6-3 6-3 win over Germany's Laura Siegemund and will play Russia's Anastasia Pavlyuchenkova or American Taylor Townsend in the last 32.

American Catherine Bellis, ranked 600 in the world and playing at her first Grand Slam in two years after four surgeries, knocked out Czech 20th seed Karolina Muchova 6-4 6-4.

Bellis, who was was told she may have to quit tennis after struggling with wrist and elbow injuries, will next face Belgian 16th seed Elise Mertens who beat Britain's Heather Watson 6-3 6-0.

Angelique Kerber, the 2016 champion in Melbourne, saw off Australian wildcard Priscilla Hon 6-3 6-2, while Carla Suarez Navarro, who will retire at the end of the season, lost 6-3 7-5 to Poland's Iga Swiatek.

Dutch ninth seed Kiki Bertens overcame Australia's Arina Rodionova 6-3 7-5 and 2019 semi-finalist Danielle Collins was beaten 6-4 2-6 7-5 by Yulia Putintseva of Kazakhstan.

Putintseva will face fourth seed Simona Halep after the Romanian two-time Grand Slam champion beat Britain's Harriet Dart.

Analysis

Jonathan Jurejko, BBC Sport at Melbourne Park

Melbourne is the city which coined the phrase - and inspired the Crowded House song - Four Seasons in One Day. On Wednesday it appeared to be monsoon season.

But, unusually, the rain band threw down a slurry-looking orangey/brown dust.

This murky torrential rain started as fans left Melbourne Park after Roger Federer's win at about 10:30pm and continued to hammer down overnight.

Apparently brought down from the dusty north, it was deposited over Melbourne and left clothes, cars and tennis courts covered in brown dirt.

Most strikingly it turned the city's arterial Yarra river - called the 'upside down' river because of its high turbidity - looking even slurrier than usual.

For the Australian Open, it meant a clean-up operation powered by jet-streamed hoses and squeezy mops on the courts - although it begged the question why covers are not used in these situations.

As one tennis fan quipped on Twitter, the clay season came early.