The training camp comes ahead of Yamanaka's 7th WBC Bantamweight title defence which is being arranged for October, though no opponent, date or venue has yet been set in stone.
Interestingly the same paper reports that Yamanaka's 7th defence could come on a show in Japan that could also feature WBC Super Featherweight champion Takashi Miura (27-2-2, 20) defending his belt for the third time and also fellow Teiken fighter Takahiro Ao (26-3-1, 12).
If these plans are announced, as speculated, then it rules out the much rumoured bout between Miura and Orlando Salido (41-12-2-1, 28) which was thought to be likely to take place in Singapore. It's a shame if we don't get Miura Vs Salido but with an October date it could mean that we could see Miura facing another name he has long been linked with, that of Britain's Stephen Smith (20-1, 12).
As well as the speculation on Yamanaka's next bout we've also been informed that he was "inspired" and "enviable" of Tomoki Kameda who of course retained his WBO Bantamweight title in Las Vegas this past weekend with a stunning knockout of Pungluang Sor Singyu. It would seem likely with that being said that Yamanaka will try to make his US debut in his next fight or two as he looks to prove his skills against the best.
(Image courtesy of Teiken)