Masaaki Koyama (小山 正明, Koyama Masaaki; July 28, 1934 – April 18, 2025) was a Japanese professional baseball pitcher in Nippon Professional Baseball (NPB). 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. He is a member of the Japanese Baseball Hall of Fame. 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 won 20 or more games 7 separate times, was selected to eleven All-Star teams, and won the 1962 Eiji Sawamura Award.
Source: “Masaaki Koyama”, English Wikipedia (CC BY-SA 4.0), excerpt