Top-seeded Sara Errani of Italy reached the semifinals of the Rio Open Friday after Beatriz Haddad Maia of Brazil retired in the deciding third set.
Maia, who won took the first set, stopped with the score 3-6, 7-6 (2), 3-0 in Errani's favor.
Errani will face No. 5 Johanna Larsson of Sweden, who defeated Dinah Pfizenmaier of Germany 6-4, 6-0.
Second-seeded Irina-Camelia Begu of Romania made the last four, beating Julie Glushko of Israel 6-1, 6-2. Begu will play No. 6 Anna Schmiedlova of Slovakia Saturday. She beat Veronica Cepede Royg 6-3, 6-1.
On the men's side of the WTA-ATP combined event, No. 1 Rafael Nadal of Spain plays late against No. 6 Pablo Cuevas of Uruguay for a semifinals berth. No. 2 David Ferrer faces Juan Monaco of Argentina.