Keys, the No. 19 seed and a two-time semifinalist at Melbourne Park, had won the first set. But Rybakina, who like Keys is a precise winner machine when she is playing the tennis she wants to play, had taken the second by seizing the initiative and playing on her front foot. Halfway to the finish, Keys had become a passive counterpuncher.

Swiatek’s latest lopsided win came via a 6-1, 6-2 scoreline in the quarterfinals against No. 8 seed Emma Navarro on Wednesday.

Madison Keys was on the ropes, but rallied on Wednesday to keep hope alive for an All-American semifinal at the Australian Open. No. 28 Elina Svitolina struck first against the 12th-seeded Keys, but Keys secured a 3-6,