Not enough days in 1999 season to compile WAA record.
| Date | Rank | WAA | TeamID |
|---|---|---|---|
| 19990416 | XXXXX | 1.08 | BAL |
| 19990430 | XXXXX | -0.73 | BAL |
| 19990514 | XXXXX | 0.00 | BAL |
| 19990528 | XXXXX | 1.20 | BAL |
| 19990611 | +082+ | 1.81 | BAL |
| 19990625 | +032+ | 3.40 | BAL |
| 19990709 | +037+ | 3.51 | BAL |
| 19990726 | +024+ | 4.59 | BAL |
| 19990809 | +040+ | 4.32 | BAL |
| 19990823 | +035+ | 4.97 | BAL |
| 19990906 | +041+ | 4.95 | BAL |
| 19990920 | +060+ | 4.53 | BAL |
| 19991004 | +038+ | 5.81 | BAL |
Mike Mussina Post Season Games
| Rank | WAA | IP | ERA | Gs | Gr | Tm |
|---|---|---|---|---|---|---|
| XXXXX | 1.06 | 42.7 | 2.53 | 6 | 0 | BAL |
| XXXXX | -0.48 | 97 | 3.8 | 15 | 2 | NYA |
| XXXXX | 0.58 | 139.7 | 3.42 | 0 | 0 | TOT |
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