ZAGREB – Teenage national champion Jun Mizutani pulled off an upset win in the men’s singles to join fellow Japanese representatives Yo Kan, Ai Fukuhara and Sayaka Hirano in the third round at the world table tennis championships on Wednesday. High school student and German Bundesliga player Mizutani, who is ranked 94th in the world, lived up to his billing as a giant killer eliminating 12th-ranked Li Ching of Hong Kong with an 11-9, 11-7, 12-10, 11-3 victory in the second round. “I was in pretty good shape to the degree that I amazed myself,” said the 17-year-old, who is known for beating Taiwanese No. 1 Chuan Chih-yuan in his world championship debut two years ago in Shanghai. Mizutani’s scalps from recent international tournaments also include reigning Olympic champion Ryu Seung Min of South Korea.