Former Japan national judoka Kosuke Mashiyama announced on 28 August on Instagram that he has acquired Mongolian nationality and will compete for Mongolia at the World Championships and the Olympics. The 27-year-old from Tokyo said he took Mongolian citizenship in July this year, a decision he described as the path to becoming an Olympic champion.
Mashiyama is best known for his forward throws. He competed at the 2022 World Championships in Tashkent, where he reached the round of 16 in the under-90 kg division, and was again selected for the 2023 Japan team. In early 2023, however, he was removed from the national squad and lost his intensive-training designation after failing a weigh-in at an international event. He returned to competition months later and switched up to the under-100 kg class, winning the All-Japan Selected Weight-Category Championships in 2024 in that division.
The decision to represent Mongolia came after approaches from the Mongolian judo federation. His parents are both Japanese and he has no Mongolian roots. Under IJF eligibility rules, he will be able to appear for Mongolia from April next year.
Mashiyama said on his Instagram that the change was his own choice, explaining that he wants to "aim once more for the top of the world through the path given to me."