Japan's world No. 4 Naomi Osaka started off the Toray Pan Pacific Open with a win, defeating Viktoriya Tomova of Bulgaria on Wednesday to reach the quarterfinals of the WTA Premier tournament held in the city of her birth.Osaka, the top seed, fought back to claim a 7-5, 6-3 victory over the Bulgarian qualifier on Center Court at ITC Utsubo Tennis Center. A beaten semifinalist in two of the last three years, when the tournament was held in Tokyo, Osaka faces a best-eight match with either Russia's Varvara Flink or Kazakhstan's Yulia Putintseva.Related coverage:READ FULL ARTICLE
