Mogi was named a tourism ambassador for Koganei, Tokyo (his hometown) in 2018. His term will be for two years, from January 18, 2018 until January 17, 2020.
October 15, 2017 vs Seibu at MetLife Dome – Mogi recorded a home run off the first pitch of the game and joined Takumi Kuriyama (2005) and Ikuhiro Kiyota as the only players to accomplish the feat during Playoff/Climax Series play.
October 18, 2017 vs Softbank at YafuOku Dome – Mogi hit the third pitch of the game, a 1-1 fastball, over the fence in left-center for his second lead-off home run this Climax Series. He joined Ikuhiro Kiyota (2016) as the only players to record two Climax Series lead-off home runs during one post-season.