Four Japanese players advanced to the last eight at the Guam Futures tennis tournament.
Jun Ito beat local hope Daniel Llarenas 6-1 6-3, while second seed Toshihide Matsui was too good for American Joseph Kasnetz.
Shinta Fujii and third seed Junn Mitsuhashi also advanced, as did Korean top seed Daniel Yoo, who had a straight sets win over another Japanese player, Shoki Hachiya.
