From what we understand the session was more about shaking off some built up ring rust for Yamanaka who is set to travel to the US next month for a small training camp in Los Angeles. That camp will likely focus on technical aspects whilst letting Yamanaka hae a second "dry run" of conditions in the US, allowing himself to get used to the time zone difference, the food and general culture with the plan to make his US debut sooner rather than later.
Prior to a US debut it's thought that Yamanaka will be fighting in October in the 7th defence of his world title. No opponent has yet been named though our Thai source has suggested that the WBC will be calling a mandatory between Yamanaka and Suriyan Sor Rungvisai (37-5-1, 16). We're unsure if the WBC will do that or not though it's certainly one possibility for Yamanaka who has been out of the ring since he stopped Belgium's Stephane Jamoye earlier this year.