Veronika Kudermetova and Paula Badosa both pulled out of their Adelaide International semifinals with injury problems on Friday, leaving them in a race to be fit for the Australian Open.
Their withdrawals gave Belinda Bencic and Daria Kasatkina free rides into Saturday's title match.
Russia's Kudermetova, seeded nine for the opening Grand Slam of the year, which starts on Monday, cited a left hip injury for her pull-out against Switzerland's Bencic.
It followed epic three-setters in her two previous matches, with her quarterfinal against Danielle Collins on Thursday extending beyond three hours.
Olympic champion Bencic, who has won nine of her last 10 matches, is aiming to claim a sixth singles trophy and her fifth on a hard court.
She will face world number eight Kasatkina, who is gunning for a seventh WTA title and her second in Australia, having claimed the Phillip Island Trophy last year.
Kasatkina progressed when Spain's Paula Badosa, seeded 11th at Melbourne Park, opted out because of a thigh injury.
"Yesterday when I was playing it was a very tough match, especially physical, so I felt a little bit in my abductor. I felt like I pulled it a little bit," said Badosa.
The Spaniard battled through a gruelling quarterfinal clash with Brazil's Beatriz Haddad Maia that stretched beyond two-and-a-half hours.
"Today I feel a little bit worse, I have the Australian Open ahead, and I hope I can recover for that," she added.
The Grand Slam has been hit by numerous withdrawals in both the men's and women's fields, including two-time former champion Naomi Osaka, who is expecting her first child.
In the men's draw, South Korea's Kwon Soon-woo dominated from the baseline to overpower Britain's Jack Draper 7-6 (8/6), 6-7 (2/7), 6-3 and surge into the final.
Kwon lost to Draper - who is Rafael Nadal's first-round opponent at the Australian Open - in the first of two Adelaide tournaments and was set to miss this week's event after defeat to Tomas Machac in the final round of qualifying.
But he sneaked in as a lucky loser and is now in a final against either Australia's Thanasi Kokkinakis or Spaniard Roberto Bautista Agut.
"It was a very difficult match today," said Kwon. "I'm just really happy to win today... Last week he played very well, so I tried to just enjoy this match and be positive. I tried to be more aggressive."