The field for the final knockout stage of the men’s individual event is set, and one amateur is in it. In block F, Li Xianyu of Canada nosed out Wang Mingwan (O Meien) of Chinese Taipei on sum of opponents’ scores (SOS) to earn a place among the best sixteen.

Li (left) vs Sakai

He joins five pros from the Republic of Korea, four from China, three from Japan, and three from Chinese Taipei.

It was almost two amateurs. Matthew Macfadyen of the U.K. and Li Zhe of China finished with five wins apiece in block G. They were also even on SOS. The tie was broken by SOS-1 points, which is SOS excluding the opponent in the randomly drawn first round. In that round Macfadyen had been matched against Korean Park Younghun, who finished with a perfect 6-0 score, while Li had drawn Emilio Gutierrez Galicia of Mexico, who ended up at 3-3. Deducting these points put Li ahead of Macfadyen on the basis of the performance of their opponents in the progressively less randomly drawn rounds two to six, but when all this was explained, Macfadyen got a well-deserved round of applause.

Tie breaks were needed in two other blocks as well. In block E Yamashiro Hiroshi topped Michael Redmond of the USA by five SOS points, and in block B, Lee Yi-hsiu of Chinese Taipei edged out Zhou Ruiyang of China by a single SOS point.

The SOS-1 second-level tie break has much merit. Opinions may vary, but to this writer it makes more sense than sum of defeated opponents’ scores (SODOS), and it is a lot easier to calculate than sum of opponents’ SOS (SOSOS). If necessary, it also extends easily to deeper tie-breaking levels: SOS-2, SOS-3,…. A tip of the hat to Jin Tongshi, Director of the WMSG Technical Office, for introducing this system from the world of chess into the world of go.

In the women’s individual event Australia’s undefeated duo of Joanne Missingham and Cathy Zhang remains undefeated. Rui Naiwei of China survived a risky endgame ko fight to defeat Hwang Kyongju of DPR Korea. In pro-pro matches, Cao Youyin (China) beat Pan Kunyu (Chinese Taipei), He Xiaoren (Canada) beat Kan Ying (Hong Kong China), and Lee Minjin (Republic of Korea) beat Ina Akiko (Japan, better known by her maiden name, Tsukuda Akiko).

In the all-amateur open event, Ham Youngwoo of the Republic of Korea bested Mori Hironobu of Japan, Jo Saebyol of DPR Korea beat Yen Tingyu of Singapore, Merlijn Kuin of The Netherlands beat Tony Goddard of the U.K., and Russia’s Ilya Shikshin downed Germany’s Zhao Pei. Americans had mixed success: Jie Li defeated Huang Chao of Hong Kong China, but Joey Hung lost to Wang Chen of China.

– James Davies