SEOUL, South Korea — Beatriz Haddad Maia advanced to the rain-delayed semifinals of the Korea Open with a 6-2, 6-1 win over Polina Kudermetova on Saturday.

Haddad Maia was the 2017 runner-up in the Seoul WTA 500-level tournament.

Persistent rain showers washed out all play Friday, forcing the quarterfinals and semifinals to be played on Saturday.

Kudermetova, 21, played Haddad Maia on Centre Court at the same time her sister Veronika Kudermetova, who is 27 and ranked 25th, was taking on Viktoriya Tomova on the Grandstand Court. The elder Kudermetova had a better result for the family, with Veronika beating Tomova 7-5, 6-3.

Haddad Maia was scheduled to play Veronika Kudermetova in the first semifinal later Saturday with a chance to beat both Kudermetova sisters on the same day.

In a later quarterfinal, top-seeded Daria Kasatkina advanced when former US Open champion Emma Raducanu retired with an apparent left foot injury after losing the first set 6-1.

Kasatkina had not lost a set to Raducanu in two previous meetings, including a 6-2, 6-2 win in the Eastbourne grass-court quarterfinals three months ago. Raducanu was bidding to reach her first semifinal above WTA 250 level since winning the 2021 US Open.

In the other quarterfinal, fourth-seeded Diana Shnaider played fifth-seeded Marta Kostyuk. The winner will play Kasatkina in the semifinals.