Yasuhiro Yamashita, Seigo Saito, Yasuyuki Muneta, and Yohei Takai are the only other judoka in history who received the award four times.

Masaki continued to work and train at the university after graduating, but was unable to gain a spot on the Japanese national judo team as the third-string competitor behind Yasuhiro Yamashita and Hitoshi Saito.

Masaki filled in as a last-minute replacement, and defeated Mohamed Rashwan in the final to become world champion in the Open weight category.

[2] He continued his success with consecutive wins at the All-Japan Judo Championships from 1986 to 1987, and was scheduled to enter the 1987 World Judo Championships but withdrew due to an injury (his replacement, 19-year-old Naoya Ogawa, went on to win the tournament to become the youngest world champion at the time).

Masaki has continued to work for Tenri University after retiring, both as a judo instructor and a professor in sports science.