OSAKA, Japan (AP) — American teenager Madison Keys reached the quarterfinals of the Japan Women’s Open with a 6-0, 6-4 victory over Misaki Doi on Wednesday.

The second-seeded Keys was broken twice in the second set but still managed to win. The 19-year-old American will next face Luksika Kumkhum of Thailand. Kumkhum beat Eri Hozumi 2-6, 6-4, 6-4.

Heather Watson of Britain, the champion two years ago, lost to Yulia Putintseva of Kazakhstan 6-4, 7-5, while third-seeded Elina Sviotlina of Ukraine defeated Japanese wild-card entry Naomi Osaka 3-6, 6-3, 6-4.

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