| Hack Spencer | |
| Position: | Pitcher |
| Bats: | Right |
| Throws: | Right |
| Birth Date: | 25 April 1885 |
| Birth Place: | St. Cloud, Minnesota |
| Death Place: | St. Anthony, Minnesota |
| Debutleague: | MLB |
| Debutdate: | April 18 |
| Debutteam: | St. Louis Browns |
| Finalleague: | MLB |
| Finaldate: | April 18 |
| Finalteam: | St. Louis Browns |
| Statleague: | MLB |
| Stat1label: | Games |
| Stat1value: | 1 |
| Stat2label: | Win–loss record |
| Stat2value: | 0–0 |
| Stat3label: | Earned run average |
| Stat3value: | 0.00 |
| Teams: | |
Fred Calvin "Hack" Spencer (April 25, 1885 – February 5, 1969) was an American professional baseball player. Spencer played for the St. Louis Browns in the 1912 season. In one career game, he pitched in 1.2 innings and gave up two hits and two runs. He batted and threw right-handed.
Spencer was born in St. Cloud, Minnesota, and died in St. Anthony, Minnesota.