Japan's former World No. 1 Naomi Osaka reached the quarterfinals of the DC Open for the first time, while compatriot and former No. 4 Kei Nishikori exited in the second round on Wednesday.Osaka advanced from the women's singles second round after American opponent Ashlyn Krueger retired with a right ankle injury while trailing the four-time Grand Slam winner 6-3, 3-1.Having won all her majors on hardcourts, Osaka is coming off her best-ever Wimbledon result after reaching the quarterfinals in London earlier this month.Asked about the performance in her post-match press conference, Osaka rep…READ FULL ARTICLE