Emma Navarro, the eighth seed from the United States, joined the Pole in the next round with a gritty three-set win over Ons Jabeur.

Sixth seed Elena Rybakina also advanced despite a back problem.

"I felt like the ball is listening to me," Swiatek said after rattling off 11 straight games in a brutal display against Britain's Raducanu on Rod Laver Arena.

The 23-year-old Swiatek is a five-time major winner but she has never gone beyond the semi-finals at Melbourne Park.

She faces world number 128 German Eva Lys next.

Lys beat Jaqueline Cristian of Romania in three sets to become the first women's singles "lucky loser" to reach the fourth round since the event moved to Melbourne Park in 1988.

Navarro credited her billionaire father for teaching her "toughness" as she clawed through 6-4, 3-6, 6-4 against three-time Slam finalist Jabeur.

No WTA player has played more three-set matches since the beginning of 2024 than Navarro, with the American having a 23-9 win-loss record over the distance since then.

Former Wimbledon champion Rybakina of Kazakhstan needed a medical timeout to treat a back spasm before winning 6-3, 6-4 against Dayana Yastremska of Ukraine.

Asked if her back would be OK, she replied: "Not really. So I will see my physio and hopefully he does some magic."

American Danielle Collins, who has become the pantomime villain after thanking hecklers for "paying my bills", is also in action.

The world number 11, runner-up in the 2022 Australian Open final to Ash Barty, gets another chance to wind up the Australians in the crowd when she faces fellow American Madison Keys.