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 will face No. 19 Madison Keys of the U.S. on Thursday night for a berth in the final. The other women’s semifinal is No. 1 Aryna Sabalenka, the two-time defending champion, against her good friend, No. 11 Paula Badosa.

The semifinal matches are scheduled to start at 3:30 a.m. EST and will be broadcast on ESPN and ESPN Deportes. Fans looking to watch can do so through FuboTV, which offers a free trial and $30 off your first month, or DirecTV Stream, which also offers a free trial. SlingTV doesn’t offer a free trial but does have other promotional offers available.