Hamamatsu is a bit of a Brazilian enclave http://en.wikipedia.org/wiki/Hamamatsu , which does give the story an air of plausibility, but I do wonder if there is much more to this than we currently know. They might have been an easy scapegoat in the mind of Jerry (Yakuza probably being invisible to the likes of him).
As a Kiwi who lived in Japan I must confess to being unable to uncover any rugby whilst there – it’s essentially non existant, and seems to be a legacy of the old hedonistic capitalist days of big Japan. These days it’s not clear how the companies involved can continue to justify such an indulgence.
Indeed Jerry’s team’s name is Yamaha Júbilo – Júbilo being Portuguese for Joy