| ERA* Wins Losses Saves Games Games Started Complete Games Shutouts Innings Pitched Hits Allowed Homeruns Allowed Strikeouts Walks Allowed |
| Boston Losses - Career Leaders |
| Rank | Player | Value |
| 1 | Lefty Leifield | 11 |
| 2 | Carl Lundgren | 10 |
| 3 | Rube Foster | 9 |
| Al Demaree | 9 | |
| Jim Hearn | 9 | |
| 4 | Whit Wyatt | 8 |
| Red Munger | 8 | |
| 5 | Jim Bunning | 7 |
| Randy Gumpert | 7 | |
| 6 | Barney Pelty | 5 |
| George Mullin | 5 | |
| Noodles Hahn | 5 | |
| 7 | Elmer Ponder | 3 |
| Jeff Tesreau | 3 | |
| Paul Derringer | 3 | |
| Nick Altrock | 3 | |
| 8 | Lady Baldwin | 2 |