| Tm | Name | W | L | Start | End | |
|---|---|---|---|---|---|---|
| BOS | Johnny Kling | 52 | 101 | Beg | End | |
| BOS | Jake Stahl | 105 | 47 | Beg | End | |
| CHA | Nixey Callahan | 78 | 76 | Beg | End | |
| CHN | Frank Chance | 91 | 59 | Beg | End | |
| CIN | Hank O'Day | 75 | 78 | Beg | End | |
| CLE | Harry Davis | 54 | 71 | Beg | 19120901 | |
| CLE | Joe Birmingham | 21 | 7 | 19120902 | End | |
| DET | Hughie Jennings | 69 | 84 | Beg | End | |
| LAN | Bill Dahlen | 58 | 95 | Beg | End | |
| NYA | Harry Wolverton | 50 | 102 | Beg | End | |
| OAK | Connie Mack | 90 | 62 | Beg | End | |
| PHI | Red Dooin | 73 | 79 | Beg | End | |
| PIT | Fred Clarke | 93 | 58 | Beg | End | |
| SFN | John McGraw | 103 | 48 | Beg | End | |
| SLN | Roger Bresnahan | 63 | 90 | Beg | End | |
| SLN | Bobby Wallace | 12 | 27 | Beg | 19120601 | |
| SLN | George Stovall | 41 | 74 | 19120602 | End | |
| TEX | Clark Griffith | 91 | 61 | Beg | End |
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