Atsushi Ugumori hit a three-run homer and Yuya Fukui pitched a six-hit shutout Monday as tournament favorite Saibi beat Iwakuni of Yamaguchi Prefecture 6-0 to ease into the quarterfinals of the National High School Baseball Championship.
Ugumori's second homer of the tournament helped Saibi, winner of the national invitational championship this spring, take a five-run lead after three innings and the Ehime Prefecture school cruised to victory in the third-round game at Koshien Stadium.
Komadai Tomakomai of Hokkaido, Tokyo's Shutoku and Tenri from Nara Prefecture also booked their places in the last eight.
Komadai Tomakomai broke a 4-4 tie with an RBI single by Yasuhito Suzuki in a three-run eighth inning and survived a late rally to edge Nichidai Daisan of Tokyo 7-6.
Shutoku blanked Sakata Minami from Yamagata Prefecture 2-0 thanks to a strong outing from southpaw Masaru Saito, who pitched his second straight complete-game shutout.
Tenri jumped on a 3-0 lead in the first inning and held on to beat Shimane's Hamada 6-1.