LaHair, 30, made the NL All-Star team in 2012 but fell into a slump as the season continued, finishing with 16 home runs and a .259/.334/.450 batting line in 380 plate appearances.
The Cubs could have traded LaHair last season when he was playing at an All-Star level but now, they would have to sent him to Triple-A or he would become a free agent. His opportunity to go to Japan could be more lucrative than if he stays which could explain the Cubs and LaHair's decision to go this route.
LaHair, who plays both corner outfield and first base, would get lost in the shuffle of the Cubs' roster and would see limited playing time if he stayed with the Cubs. The Cubs, meanwhile, need to get to 40-man rosters on Wednesday in time for the Rule V Draft.