Youkilis, 34, has agreed to a one-year deal with the Rakuten Golden Eagles. He will earn a $4 million salary with $1 million available in incentives.
Youkilis played parts of nine seasons for the Red Sox, hitting .287 with 133 home runs. He was a three-time All-Star and appeared in 29 postseason games. He was a Gold Glove winner at first base in 2007, helping the Red Sox to the World Series title. He broke in during the 2004 season, appearing in 72 regular-season games but not in the World Series.
In April of 2012, former Red Sox manager Bobby Valentine said during a television interview that Youkilis was not ďas physically or emotionally into the game" as he once was. Valentine was forced to apologize to Youkilis.
The oft-injured Youkilis was traded to the White Sox on June 24, 2012, after the Red Sox elected to start Will Middlebrooks at third base.
Youkilis signed a one-year, $13 million deal as a free agent with the Yankees for the 2013 season but was limited to 28 games because of injuries.
Joe Bick, Youkilis' agent, told ESPN that his client had opportunities in the majors but decided to take his family to Japan.
Youkilis' wife, Julie, is one of Tom Brady's sisters. He has two children.
Youkilis is a career .281 hitter in the majors with a .382 on-base percentage that ranks 155th all-time.
Since the start of the 2012 season, Youkilis has hit .232 with a .726 OPS.