No. 3 seed Alison Riske reached the quarterfinals of the Zavarovalnica Sava Portoroz by rallying for a 3-6, 6-3, 6-3 victory against Slovakia's Viktoria Kuzmova on Wednesday in Portoroz, Slovenia.
Riske saved nine of 12 break points and won the last three games, including two service breaks, to finish the match in two hours and 17 minutes.
Riske will next face France's Kristina Mladenovic, a 6-0, 6-4 winner against Croatia's Ana Konjuh. Mladenovic holds a 4-1 head-to-head edge over Riske, but they last met in 2017 at Wimbledon.
No. 2 seed Yulina Putintseva of Kazakhstan cruised to a 6-3, 6-1 win against Britain's Katie Boulter and Italy's Lucia Bronzetti rallied for a 2-6, 6-3, 6-3 defeat of Bernarda Pera.
BGL BNP Paribas Luxembourg Open
Denmark's Clara Tauson upended fourth-seeded Russian Ekaterina Alexandrova 6-4, 3-6, 7-6 (1) to reach the final eight in Luxembourg.
Marie Bouzkova of the Czech Republic also played the upset game, sending No. 6 seed Shuai Zhang home with a 6-2, 6-7 (3), 6-3 win in a second-round match.
Three other seeded players joined Tauson in the quarterfinals. No. 5 Marketa Vondrousova of the Czech Republic posted a 6-2, 6-4 win against Croatia's Jana Fett. No. 7 Liudmila Samsonova of Russia held off France's Oceane Dodin 7-6 (5), 7-6 (3). France's Alize Cornet, the No. 8 seed, was a 6-3, 6-3 winner against Luxembourg's Mandy Minella.
--Field Level Media