| Rank | WAA | IP | ERA | Gs | Gr | Tm |
|---|---|---|---|---|---|---|
| +051+ | 3.23 | 166.7 | 3.24 | 23 | 0 | NYN |
| Date | Rank | WAA | TeamID |
|---|---|---|---|
| 19770510 | +017+ | 1.96 | NYN |
| 19770524 | +030+ | 1.96 | NYN |
| 19770607 | +028+ | 2.35 | NYN |
| 19770621 | +039+ | 2.60 | NYN |
| 19770705 | +044+ | 2.76 | NYN |
| 19770722 | +045+ | 3.23 | NYN |
| 19770803 | +051+ | 3.23 | NYN |
| 19770807 | +055+ | 3.19 | NYN |
| 19770821 | +043+ | 3.84 | NYN |
| 19770904 | +075+ | 2.97 | NYN |
| 19770918 | +081+ | 3.06 | NYN |
| 19771002 | +097+ | 2.89 | NYN |
Jerry Koosman Post Season Games
| Rank | WAA | IP | ERA | Gs | Gr | Tm |
|---|---|---|---|---|---|---|
| XXXXX | -0.18 | 0.3 | 27 | 0 | 1 | CHA |
| XXXXX | 0.21 | 40 | 3.38 | 6 | 0 | NYN |
| XXXXX | 0.03 | 40.3 | 3.57 | 0 | 0 | TOT |
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