Ostapenko loses 1st-round match at Korea Open to 569th-ranked Back. Pegula advances

Second-seeded Jelena Ostapenko was dumped out of Korea Open in first round by local wild card Back Da-yeon 3-6, 6-1, 7-6 (4) on Tuesday.

In her third tour-level tournament appearance, all of which have been at Korea Open, South Korean player h never vanced past first round. It looked that trend was set to continue but Back rallied from 5-2 down in third set, saving one match point, and n claimed deciding tiebreaker for biggest win of her career.

Fifth-seeded Sofia Kenin was also beaten by a home favorite, with 162nd-ranked Jang Su-jeong winning 6-1, 6-4. Jang next plays American Emina Bektas, who beat Laura Pigossi 6-7 (5), 6-4, 7-5 in a three-hour duel.

Fourth-ranked Jessica Pegula won her opening round match beating No. 74 Viktoria Hruncakova 6-2, 6-4.

Waiting for top-seeded American in next round is compatriot Ashlyn Krueger, who earlier beat Nia Podoroska 6-2, 6-4.

Also, Eva Lys beat Anna Karolina Schmiedlova 6-2, 6-4, fourth-seeded Marie Bouzkova downed Kayla Day 6-4, 6-4 and Kimberly Birrell defeated qualifier Sachia Vickery 6-4, 6-4.