Education
Koyama attended Takasuna High School, and entered NPB at age 18, drafted by the Osaka Tigers.
Koyama attended Takasuna High School, and entered NPB at age 18, drafted by the Osaka Tigers.
He played for the Osaka / Hanshin Tigers from 1953 to 1963, the Tokyo / Lotte Orions from 1964 to 1972, and the Taiyo Whales in 1973. A right-handed pitcher, Koyama threw hard and was known for his effective slider and pinpoint control. He ranks third all-time in the NPB in wins (320), strikeouts (3,159), innings pitched (4,899), and shutouts (74).
He had at least 200 strikeouts for 7 straight seasons from 1956–1962.
In 1961 Koyama suffered his first losing season, going 11-22, leading the Central League in losses despite a stellar 2.41 earned run average. In 1962, Koyama had 13 shutouts, including five in a row, on his way to a 27-11 record with a 1.66 European Research Area and the Sawamura Award.
He also led all of NPB in strikeouts, with 270. (Koyama ended up on the losing end of three Japan Series, never winning a championship)
In 1964, Koyama switched teams (and leagues) and went 30-12 for the Tokyo Orions, leading all of NPB in victories, with a 2.41.
European Research Area. That year he had 25 complete games and led all of NPB in innings pitched, with 361-1⁄3.
He was elected to the Japanese Baseball Hall of Fame in 2001. On May 2, 1992, Tsutomu Seki discovered the minor planet 1992 Journal of Economics, naming it "13553 Masaakikoyama" in honor of Koyama.
He is a member of the Japanese Baseball Hall of Fame. With 200+ wins, Koyama was a founding member of Meikyukai in 1978.