Isamu Usui (臼 井浩)
- Bats Right, Throws Right (some sources list him as R/L)
- Height 5' 6", Weight 165 lb.
- School Chuo Gakuin University
Isamu Usui pitched for Tokyo Gas in the industrial leagues after college. He went 6-0 in 2017 to lead the industrial leagues in wins.  He was stellar for the Japanese national team that won Silver in the 2018 Asian Games. Starting against China, he allowed a leadoff hit to Zhenhong Lu but then retired nine in a row before Takumi Takahashi relieved with a 16-0 lead. Versus South Korea, he closed out a 5-1 loss, replacing Akiyoshi Katsuno and striking out former major leaguer Jae-gyun Hwang with the bases loaded to end the top of the 9th. He tied Lai-Him Lam and Tsung-Hao Wang for the best ERA among non-qualifiers in the main round of the Games. In the Gold Medal Game, he relieved Takahashi in the 5th with a 3-0 deficit against South Korea. He got Jung-hoo Lee on a fly, walked Ha-seong Kim but retired the next five, three by strikeout, including Ks of two more ex-MLB players, Byung-ho Park and Hyun-soo Kim.