Okajima has spent his entire MLB career with the Boston Red Sox after signing with them in 2007 and winning a World Series. After struggling last season and ending up with the Pawtucket Red Sox in Triple A, he became a free agent this off season.
He had signed with division rival New York Yankees in the fall. He then failed a physical with the Yankees this spring because of a left shoulder injury. He downplayed his injury concerns to the Japan media and said that he is ready to show what he showed in 2007 with the Red Sox.
He will be back in Japan for the first time since 2006. He had an earned run average of 3.11 in his Red Sox career.