Yamanaka improved his record to 27-0-2 by dropping Carlos Carlson five times on his way to a comprehensive victory in front of his home fans.
The champion proved dominant throughout, although credit has to go to Carlson for continually getting to his feet. Carlson drops to 22-2 but can come again after showing considerable heart.
For Yamanaka, the win cements his place as the top 118 pounder on the planet but doesn’t do him any favors in his quest to unify.
Not many bantamweight operators would fancy their chances in the Land of the Rising Sun on this evidence.
Britons Jamie McDonnell and Lee Haskins currently hold the WBA and IBF versions respectively, whilst Kazakh Zhanat Zhakiyanov is the World Boxing Association’s ‘super’ champion. Currently in possession of the WBO strap is Marlon Tapales of the Philippines, whilst the IBO belt is vacant after Zhakiyanov failed to pay the sanction fee following his win over Rau’shee Warren recently.
In the co-feature, Kenichi Ogawa defended his Japanese super-featherweight title with a majority decision win over Satoru Sugita, whilst former world title holder Brian Viloria pushed towards another shot at a recognised title with a unanimous triumph over Ruben Montoya at super-flyweight.
