| Starter | Tm | Tier | Game |
|---|---|---|---|
| Ray Sadecki | SLN | -2.58 | 196309030_PIT_SLN |
| Jim Bunning | DET | -2.36 | 196309030_NYA_DET |
| Tracy Stallard | NYN | -2.21 | 196309030_CIN_NYN |
| Steve Ridzik | TEX | -1.55 | 196309050_TEX_NYA |
| Cal Koonce | CHN | -0.87 | 196309040_CHN_LAN |
Based on accumulated WAA for this season up to 1963-09-05.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +002+ | 9.18 | Sandy Koufax | 265.3 | LAN |
| +003+ | 8.17 | Dick Ellsworth | 249.7 | CHN |
| +004+ | 8.06 | Gary Peters | 214.7 | CHA |
| +005+ | 7.92 | Bob Friend | 243 | PIT |
| +010+ | 6.07 | Juan Marichal | 268 | SFN |
| +012+ | 5.94 | Larry Jackson | 240.3 | CHN |
| +017+ | 5.35 | Juan Pizarro | 215 | CHA |
| +019+ | 5.09 | Warren Spahn | 218.7 | ATL |
| +023+ | 4.83 | Camilo Pascual | 205.7 | MIN |
| +024+ | 4.82 | Steve Barber | 234.3 | BAL |
| +025+ | 4.81 | Jim O'Toole | 226.3 | CIN |
| +026+ | 4.79 | Don Drysdale | 278.7 | LAN |
| +027+ | 4.67 | Jim Bouton | 220.3 | NYA |
| +035+ | 4.08 | Jim Maloney | 212.3 | CIN |
| +037+ | 3.8 | Joe Nuxhall | 181 | CIN |
| +039+ | 3.65 | Al Downing | 145.7 | NYA |
| +042+ | 3.53 | Curt Simmons | 201.3 | SLN |
| +045+ | 3.31 | Denny Lemaster | 207 | ATL |
| +054+ | 3.04 | Milt Pappas | 197 | BAL |
| +061+ | 2.94 | Lee Stange | 126 | MIN |
| +065+ | 2.76 | Tom Cheney | 136.7 | TEX |
| +069+ | 2.6 | Ray Culp | 182 | PHI |
| +070+ | 2.53 | Don Cardwell | 197.7 | PIT |
| +073+ | 2.47 | Ken McBride | 239.7 | ANA |
| +076+ | 2.4 | Billy O'Dell | 188.7 | SFN |
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