"That means it works," Castillo said of his style.
Castillo didn't catch the Japanese pitcher much in Spring Training, but learned what Fujikawa wanted when they talked before a game. What if the hitter sees where Castillo is set and anticipates the pitch?
"They might know," Castillo said. "We can change it, too."
Fujikawa has a variety of other pitches, and Castillo is learning what the right-hander likes to throw in certain situations and how to set up for those, too.
"That's why this game is interesting," Castillo said.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.