Yamaguchi had little trouble making her way past young Korean Kim Hyang Im .
Mitani had to struggle hard to overcome China 's Chen Yufei , 14 - 21 21 - 19 21 - 16 .
Yamaguchi had little trouble making her way past young Korean Kim Hyang Im , but Mitani had to struggle hard to overcome China 's Chen Yufei , 14 - 21 21 - 19 21 - 16 .