Sabalenka, the second seed, has had to work hard for her place in the second week, having come back from a set down to win in her last three matches.

This time the Belarusian turned things around against Marketa Vondrousova to secure a 4-6 6-3 6-1 victory.

Sabalenka has been struggling with her serve and hit 10 double faults to just one ace on the Margaret Court Arena.

"I'm really happy right now, mostly I'm happy I made only 10 double-faults," Sabalenka said, laughing, in her on-court interview. "I'll just keeping working on the serve and hope it gets better with every match."

Sabalenka now faces world No 115 Kaia Kanepi, who beat Australian Maddison Inglis 2-6 6-2 6-0.

Kanepi has reached the quarter-finals six times at Grand Slam events, but has never reached the last eight at the Australian Open.

Elsewhere in the draw, the 27th seed Danielle Collins also rallied from a set and a break down to beat 19-year-old Clara Tauson 4-6 6-4 7-5.

Collins' fourth-round opponent is Elise Mertens, who needed just 70 minutes on court to win 6-2 6-2 over Zhang Shuai.

Former French Open champion Iga Swiatek dominated from the baseline to overcome Daria Kasatkina 6-2 6-3 and book her place in the fourth round.

The 23rd-ranked Kasatkina won the pair's only previous meeting in 2021, however that match was played on grass.

Swiatek hit 24 winners and broke Kasatkina's serve twice in each set to determinedly push through the contest on Margaret Court Arena in one hour and 34 minutes.

The 20-year-old will next meet either Anastasia Pavlyuchenkova or Sorana Cirstea of Romania for a place in the quarter-finals at Melbourne Park