Kadokura, 35, a right-hander, agreed to a Minor League contract with a non-roster invitation to Spring Training.
He has a career 76-82 record and 4.36 ERA in 302 games, including 172 starts, for the Chunichi Dragons, Osaka Kintetsu Buffaloes, Yokohama Bay Stars and Yomiuri Giants.
Kadokura's lone Japan Series appearance was in 1999 with Chunichi, when he was a teammate of Cubs outfielder Kosuke Fukudome.
Kadokura has averaged eight strikeouts per nine innings pitched, and posted four seasons with at least 10 wins. His best season was 2005 with Yokohama when he was 11-8 with a 3.37 ERA in 29 games.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.