| Mack Stewart | |
| Position: | Pitcher |
| Bats: | Right |
| Throws: | Right |
| Birth Date: | 23 September 1914 |
| Birth Place: | Stevenson, Alabama |
| Death Place: | Macon, Georgia |
| Debutleague: | MLB |
| Debutdate: | July 7 |
| Debutyear: | 1944 |
| Debutteam: | Chicago Cubs |
| Finalleague: | MLB |
| Finaldate: | June 22 |
| Finalyear: | 1945 |
| Finalteam: | Chicago Cubs |
| Statleague: | MLB |
| Stat1label: | Win–loss record |
| Stat1value: | 0–1 |
| Stat2label: | Earned run average |
| Stat2value: | 3.76 |
| Stat3label: | Strikeouts |
| Stat3value: | 12 |
| Teams: |
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William Macklin Stewart (September 23, 1914 – March 21, 1960) was a pitcher in Major League Baseball (MLB) who played during 1944 and 1945 for the Chicago Cubs.
Stewart's only MLB decision came on May 29, 1945, when the Cubs hosted the Brooklyn Dodgers at Wrigley Field. Stewart was the starting pitcher, but allowed 6 runs in only 2 innings; the Cubs would lose 10–3.[1]