Plíšková smashed two racquets in a 7-5, 7-5 defeat to fellow Czech Karolína Muchová on an empty Rod Laver Arena.

Top seed Barty fell behind in both sets before overcoming Russian Ekaterina Alexandrova 6-2, 6-4.

It was the first of five days which will be held without fans after the state of Victoria announced a snap lockdown yesterday to combat the spread of coronavirus.

But Barty said she was able to see advantages of playing without a crowd on the Margaret Court Arena.

"It doesn’t change for me," said Barty.

"Obviously tonight was something I have never experienced before.

"I almost had to cut myself some slack and give myself the time to get used to it and adjust to it.

"You can narrow your focus in to listen to the sound of the ball.

"I find it a way where I can listen to the spin the opponent is hitting on the ball, the pace it’s coming."

Barty is scheduled to meet American Shelby Rogers, who defeated Anett Kontaveit of Estonia 6-4, 6-3.

There was also an emphatic victory for fifth seed Elina Svitolina of Ukraine who lost just four games in a 6-4, 6-0 thrashing of Kazakstan's Yulia Putintseva.

Svitolina’s triumph sets up a fourth-round clash with American Jessica Pegula, who continued her superb run with a 6-2, 6-1 demolition of France’s Kristina Mladenovic.

Kaia Kanepi’s hopes of backing up her stunning win over reigning champion Sofia Kenin were dashed by Croatia’s Donna Vekić.

The Estonian took the first set and came within a point of victory before Vekić pulled off a gutsy three-set comeback, winning 5-7, 7-6 (7-2), 6-4.

Vekić is now due to face Jennifer Brady for a quarter-final berth after the American thumped Slovenian qualifier Kaja Juvan 6-1, 6-3.

Belgian 18th seed Elise Mertens reached the second week of a major for the eighth time of her career following a 6-2, 6-1 victory over 11th seed Belinda Bencic of Switzerland.

In the men’s side of the draw, fourth seed Daniil Medvedev was taken to a decider after letting slip a two-set lead before overcoming Filip Krajinović of Serbia.

The Russian’s coach Gilles Cervara walked out during the contest before his charge went on to clinch a 6-3, 6-3, 4-6, 3-6, 6-0 victory.

"He said just before leaving that he's sure I'm going to win the match, but he's going to leave to let me be more calm," Medvedev said after the eventful win.

"Sometimes maybe I will disagree but this time for sure it was a good thing to do.

"Today it helped, and definitely we're going to talk about it a little bit, but there is not a big deal."

There were no such problems for 20-time major winner Rafael Nadal who powered into the fourth round.

The Spaniard beat Britain’s Cameron Norrie 7-5, 6-2, 7-5 to set up a meeting with Italy’s Fabio Fognini, who impressed in a 6-4, 6-3, 6-4 victory over Australia’s Alex de Minaur.

Greek fifth seed Stefanos Tsitsipas took little more than 90 minutes to see off Sweden’s Mikael Ymer 6-4, 6-1, 6-1 on the John Cain Arena.

Matteo Berrettini will be Tsitsipas’ next opponent after the Italian came out on top in three straight tiebreaks against Russian Karen Khachanov, winning 7-6 (7-1), 7-6 (7-5), 7-6 (7-5).

Casper Rudd became only the second Norwegian man to progress to the fourth round of a major, following in his father Christian’s footsteps, after seeing off Moldova’s Radu Albot 6-1, 5-7, 6-4, 6-4.

Russian seventh seed Andrey Rublev overcame Spanish veteran Feliciano López 7-5, 6-2, 6-3, while American Mackenzie McDonald downed South African Lloyd Harris 7-6 (9-7), 6-1, 6-4.

Competition continues tomorrow.