This is a site about Pro Yakyu (Japanese Baseball), not about who the next player to go over to MLB is. It's a community of Pro Yakyu fans who have come together to share their knowledge and opinions with the world. It's a place to follow teams and individuals playing baseball in Japan (and Asia), and to learn about Japanese (and Asian) culture through baseball.
It is my sincere hope that once you learn a bit about what we're about here that you will join the community of contributors.
Michael Westbay
(aka westbaystars)
Founder
Balls have to weigh between 141.7-148.8g and have a radius between 22.9-23.5cm.
In Japan balls tend to be on the lower side of the requirements whereas in MLB the balls tend to be on the higher side of the regulations, making the MLB balls slightly heavier and bigger than the Japanese balls.
Balls used in Japan also have different "hanpatsuryoku" which in English translates to something like "pop." There is more pop in the balls. In 2004, Dragons manager Ochiai demanded balls which did not carry as far as others used because Ochiai's Dragons was a defensive team, so the Dragons started using different types of balls in their home games. Balls with less pop.