The Seibu Lions announced on December 12 that Tomoya Mori will return to Japan after he hurt his left knee. Mori felt discomfort in the knee while running out an infield grounder during a Melbourne Aces game three to four days ago.
Mori’s condition does not seem to be serious, but the Lions did not want to take any chances and decided to call him back from Australia. He will undergo tests after he returns to Japan.
Source: Tokyo Sports 12/12/2017