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Choi Min-ho won silver in mixed doubles and bronze in boys' doubles at the 1998 World Junior Championships. In the mixed doubles event, he and partner Park Kyung-hyun lost to China's Xu Jingye and Zhang Ning in the final. In the boys' doubles event, he and partner Park Jong-wook lost to South Korea's Lee Yong-dae and Hwang Ji-man in the semifinals.