Former World Championship silver medalist N Usha suffered a shock quarterfinal defeat in the Asian Women's Boxing Championship in Astana, Kazakhstan. But Indian eves have assured themselves as their medal tally swelled to eight. Priyanka Chaudhary (54kg) clinched it by the smallest of margins against Minova Ayako of Japan after fighting out a tense quarter-final bout, yesterday. Priyanka was tied 1-1 with Ayako in the opening round. Pavitra (57kg), on the other hand, had no trouble getting past another Japanese Kugimiya Tomoko 11-2. But in the light weight 60kg category Usha was knocked out. Earlier, four-time world champion M C Mary Kom (46kg), L Sarita Devi (51kg), Sonam Yadav (75kg) fought their way to the semis, while Kavita Goyat (69kg), Aswathi Mol (81kg) and Kavita Chahal (+81kg) got byes into the last-four stage. India has sent an 11 member strong team for the event, which has 16 countries in participation.