Donald Irvin Hasenmayer (April 4, 1927 – January 28, 2020) was an American professional baseball player. He was an infielder over parts of two seasons (1945–46) with the Philadelphia Phillies. For his career, he compiled a .100 batting average in 30 at-bats, with one run batted in. He was born in Roslyn, Pennsylvania and attended Abington Senior High School. He was a navy veteran of World War II. Hasenmayer died on January 28, 2020.
Don Hasenmayer
| Given name: | Donald Irvin Hasenmayer |
| Nicknames: | None |
| Primary Pos: | Secondbase |
| Hght/Wght: | 5'10" / 180 lbs |
| Bats/Throws: | R / R |
| Born: | Apr 4, 1927 in Roslyn, PA |
| Died: | Jan 28, 2020 in Warrington, PA (92 years old) |
| Debut: | May 2, 1945 |