Koshien: Japan's Field of Dreams is a documentary airing on ESPN Monday, June 29 about Japan's annual high school tournament. Japanese legends like Masahiro Tanaka, Shohei Ohtani, Hideki Matsui, and Ichiro, among others, have all turned in dominant and historic performances at Koshien. We talked to director Ema Ryan Yamazaki about the history of the tournament, the making of the documentary, the way baseball is beloved in Japan, and the Japanese stars playing in MLB today.