- Bats Right, Throws Right
- Height 5' 11", Weight 170 lb.
- High School Kushimoto High School
Ko Okamoto pitched for the Yomiuri Giants for four seasons. He played for Matsushita Denki in the industrial leagues after high school. Yomiuri took him in the second round in 1982. He debuted with the big club three years later, saving one game and allowing three runs in 6 2/3 IP. He was named Eastern League Fireman of the Year in 1986 and allowed only one run in 11 1/3 IP while with Yomiuri. Up with the Giants for his longest stretch, he had a 3-2, 4.01 record in 26 games in 1987. In the 1987 Japan Series, he tossed three shutout innings (2 H, 2 BB, 4 K) as Yomiuri lost to the Seibu Lions in six games. Okamoto allowed three runs in 5 1/3 IP in 1988. He ended his NPB career with a 3-2, 3.55 record in 46 games. Yomiuri released him at the end of the 1988 campaign, then he spent two seasons in the minors with the Seibu Lions. Okamoto later coached in the NPB minors.