Koichi Oshima

 is a retired Japanese professional baseball player from Itabashi, Tokyo, Japan. He played for the Kintetsu Buffaloes, Orix Buffaloes, and Tohoku Rakuten Golden Eagles during his professional career, and currently works as a minor league hitting coach for the Orix Buffaloes.
Oshima was a valuable switch hitter and a solid fielder, winning three Japanese golden glove awards at second base, and two Best Nine awards. He dismissed an offer to work as a coach when the Osaka Kintetsu Buffaloes and Orix BlueWave merged, and played a season with the Tohoku Rakuten Golden Eagles before becoming a coach for the Orix Buffaloes in 2006.
He won a bronze medal in the 1992 Summer Olympics before entering the Japanese professional leagues.
References.
Sports Reference