SEOUL, South Korea -- Second-seeded Jelena Ostapenko was eliminated from the Korea Open in the first round by wild card Dayeon Back 3-6, 6-1, 7-6 (4) on Tuesday.
In her third tour-level tournament appearance, all of which have been at the Korea Open in her home country, Back had never advanced past the first round. But she rallied from 5-2 down in the third set, saving one match point, and then claimed the deciding tiebreaker for the biggest win of her career.
Fifth-seeded Sofia Kenin was also beaten by a local player, with 162nd-ranked Su Jang-jeong winning 6-1, 6-4. Jang-jeong will next play Emina Bektas, an American who beat Laura Pigossi 6-7 (5), 6-4, 7-5.
Jessica Pegula won her opening match, beating No. 74 Viktoria Hruncakova 6-2, 6-4, and will next face Ashlyn Krueger, who beat Nadia Podoroska 6-2, 6-4.
Also, Eva Lys beat Anna Karolina Schmiedlova 6-2, 6-4, fourth-seeded Marie Bouzkova defeated Kayla Day 6-4, 6-4 and Kimberly Birrell eliminated qualifier Sachia Vickery 6-4, 6-4.
Zhengzhou Open
China Open finalist Liudmila Samsonova beat Tatjana Maria 6-3, 6-3 to advance to the second round of the Zhengzhou Open, while qualifier Vera Zvonareva defeated ninth-seeded Veronika Kudermetova 6-2, 7-6 (5).
Also, Petra Martic beat Magda Linette 7-6 (5), 6-1, Laura Siegemund defeated Zhu Lin 6-2, 6-3 and wild-card Bai Zhuoxuan eliminated Tamara Korpatsch 1-6, 7-6 (3), 6-1.
Top-seeded players Maria Sakkari and Ons Jabeur received a bye in the first round. Sakkari will play Zheng Qinwen in the second round, while Jabeur will face Lucia Bronzetti.
Hong Kong Open
Leylah Fernandez reached the second round of the Hong Kong Open after top-seeded Victoria Azarenka retired with the match level at 2-6, 6-3, 0-0.
Azarenka, a two-time Grand Slam champion, appeared to injure her left leg early in the second set. Despite courtside attention from the physio, she visibly struggled to serve and move freely, allowing Fernandez to level the contest.
Fernandez will next play Mirra Andreeva, 16, who beat Dayana Yastremska 6-4, 6-3 in the second round.
Also, Kamilla Rakhimova defeated eighth-seeded Varvara Gracheva 6-3, 6-2, while fifth-seeded Anna Blinkova was leading 4-6, 6-2, 5-1 when Yulia Putintseva retired from the match.
Other first-round winners included Katerina Siniakova, Priscilla Hon and Linda Fruhvirtova.