Template:Today in Baseball/May 4
- 1871 - In the first game in professional baseball league history, the Fort Wayne Kekiongas beat the Cleveland Forest Citys, 2-0. Deacon White (pictured) gets the first hit and Bobby Mathews the first win.
- 1936 - Isamu Fujii of the Osaka Tigers hits the first home run in Nippon Pro Baseball history, an inside-the-park homer against Akira Noguchi.
- 1963 - Bob Shaw commits a MLB-record five balks in a game, three in a row at one point.
- 1966 - Willie Mays breaks Mel Ott's National League home run record by hitting his 512th. Claude Osteen is the pitching victim on the record-breaking blast.
- 1975 - Bob Watson scores the one millionth run in Major League history.