| Bill Stemmyer | |
| Position: | Pitcher |
| Bats: | Right |
| Throws: | Right |
| Birth Date: | 6 May 1865 |
| Birth Place: | Cleveland, Ohio |
| Death Place: | Cleveland, Ohio |
| Debutleague: | MLB |
| Debutdate: | October 3 |
| Debutyear: | 1885 |
| Debutteam: | Boston Beaneaters |
| Finalleague: | MLB |
| Finaldate: | June 15 |
| Finalyear: | 1888 |
| Finalteam: | Cleveland Blues |
| Statleague: | MLB |
| Stat1label: | Win–loss record |
| Stat1value: | 29-29 |
| Stat2label: | Earned run average |
| Stat2value: | 3.67 |
| Stat3label: | Strikeouts |
| Stat3value: | 295 |
| Teams: |
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William Stemmyer (May 6, 1865 - May 3, 1945) was a Major League Baseball pitcher for the Boston Beaneaters and Cleveland Blues. He was nicknamed "Cannonball".[1]
In 1886 – his first and only full season in the majors – Stemmyer led the National League in strikeouts per 9 innings (6.17) and wild pitches (63).[2] [3] The 63 wild pitches is still the highest single-season total in National League history.
Stemmyer died in his hometown at age 79.