The 38-year-old served out the American, 3-6, 7-5, 7-6 (1), 6-4, for his best Grand Slam victory by ranking in his 65th appearance.

A few hours after Monfils upset ATP No. 4 Taylor Fritz, Svitolina defeated WTA No. 4 Jasmine Paolini.

Keys got the better of her childhood rival, who has become a controversial figure in Melbourne, on Rod Laver Arena, and made new fans with her ringing endorsement of the city’s coffee scene.

The German will next face Iga Swiatek, but not before assuring herself a Top 100 debut, and (at least) $420,000 in prize money.

The former world No. 4 is into the second week of a hard-court major for the first time since 2023, rallying from two sets to one down to defeat Miomir Kecmanovic on Margaret Court Arena.

Swiatek won the battle of former US Open champions in emphatic style as she looks to reach her first quarterfinal Down Under since 2022.

The defending champion confirmed a fourth-round return, 6-3, 6-4, 6-2, on Saturday night.