[2] He also won a silver medal for his division at the 2007 World Wrestling Championships in Baku, Azerbaijan, losing out to Georgia's David Bedinadze.

[3] Sasamoto is a member of the wrestling team for Sogokeibi Sports Club in Tokyo, and is coached and trained by Hideo Fujimoto.

Sasamoto made his official debut for the 2000 Summer Olympics in Sydney, where he placed second in the four-man prelim pool of the men's 58 kg class, against Bulgarian wrestler and two-time Olympic champion Armen Nazaryan, Turkmenistan's Nepes Gukulov, and Australia's Brett Cash.

He reached the knock-out stage of the competition, by winning the preliminary pool round against Peru's Sidney Guzman, and Serbia and Montenegro's Davor Štefanek.

He lost a controversial ruling to Nazaryan in the quarterfinal match, with a score of 3–5, but bounced back to clinch the fifth spot in a consolation playoff against Kazakhstan's Nurlan Koizhaiganov with a comfortable 4–0 decision.