NEW YORK (Kyodo) -- Japan's Kurumi Nara bowed out of the U.S. Open in the first round of the women's singles Monday, losing in three sets to Belgian Elise Mertens.
Nara lost 6-2, 6-7(5), 7-5 against the world No. 15 at the USTA Billie Jean King National Tennis Center. The 99th-ranked Japanese had won her opening match at the U.S. Open for the last five years.
"Since we had played a pretty physical match before, I thought I needed to strike first," Nara said. "It would have been good if I could have kicked it into a higher gear when I took the lead in the first set. That's where it made a difference with my opponent."
In other women's singles matches, world No. 1 Simon Halep suffered a straight-sets upset against Estonian Kaia Kanepi, losing 6-2, 6-4.
Japan's Naomi Osaka, the 20th seed, will face Laura Siegemund of Germany in her first-round match on Tuesday.