| Don Brennan | |
| Position: | Pitcher |
| Bats: | Right |
| Throws: | Right |
| Birth Date: | 2 December 1903 |
| Birth Place: | Augusta, Maine, U.S. |
| Death Place: | Boston, Massachusetts, U.S. |
| Debutleague: | MLB |
| Debutdate: | April 16 |
| Debutyear: | 1933 |
| Debutteam: | New York Yankees |
| Finalleague: | MLB |
| Finaldate: | September 29 |
| Finalyear: | 1937 |
| Finalteam: | New York Giants |
| Statleague: | MLB |
| Stat1label: | Win–loss record |
| Stat1value: | 21–12 |
| Stat2label: | Earned run average |
| Stat2value: | 4.19 |
| Stat3label: | Strikeouts |
| Stat3value: | 172 |
| Teams: |
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James Donald Brennan (December 2, 1903 – April 26, 1953) was a Major League Baseball pitcher who played from 1933 to 1937 with several teams. He batted and threw right-handed. Brennan had a 21–12 record with a 4.19 earned run average over 397 innings pitched in 141 career games.[1] In his final year, he pitched for the National League champion New York Giants against their crosstown rival New York Yankees, tossing 3 scoreless innings across 2 games in the 1937 World Series.[2]
Brennan was an alumnus of Georgetown University.