Kazuhiko Akiyama did it in Sasuke 4, but the course wasn't as challenging back then.
Makoto Nagano failed in 11 and 12, and then won in 17. He was also 5 seconds away from winning Viking, which IIRC noone ever won.
There hasn't been a Sasuke winner since 2011.
Dav
And, correct me if I am wrong,but is not the current Sasuke course actually more challenging than the
American version? Combined with that they do the whole thing over the course a single day in Japan,
so there is no resting up(I always liked seeing the sun starting to rise when they were going through
stage 3, or the real Mt. Midoriyama), and it is at a higher elevation than the Las Vegas set up, so has
thinner air?