| Starter | Tm | Tier | Game |
|---|---|---|---|
| Wayne Simpson | KCA | -3.98 | 197305050_KCA_MIL |
| Ron Reed | ATL | -3.63 | 197305040_ATL_PHI |
| Reggie Cleveland | SLN | -3.18 | 197305030_SLN_SDN |
| Johnny Odom | OAK | -1.34 | 197305050_OAK_CLE |
| Mike Corkins | SDN | -1.31 | 197305050_PIT_SDN |
Based on accumulated WAA for this season up to 1973-05-05.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +001+ | 3.66 | Wilbur Wood | 64.3 | CHA |
| +002+ | 2.52 | Dave McNally | 57.3 | BAL |
| +004+ | 2.25 | Bill Singer | 50.7 | ANA |
| +006+ | 2.24 | Ken Holtzman | 53.7 | OAK |
| +007+ | 2.15 | Joe Coleman | 55 | DET |
| +008+ | 2.15 | Don Sutton | 51 | LAN |
| +009+ | 2.14 | Ron Bryant | 54.3 | SFN |
| +010+ | 2.11 | Jerry Reuss | 48 | HOU |
| +012+ | 2 | Jim Barr | 42.3 | SFN |
| +013+ | 1.98 | Tom Seaver | 47.3 | NYN |
| +014+ | 1.96 | Rick Reuschel | 36 | CHN |
| +015+ | 1.77 | Bill Greif | 28 | SDN |
| +019+ | 1.65 | Rudy May | 33 | ANA |
| +026+ | 1.49 | Jerry Koosman | 41.3 | NYN |
| +027+ | 1.44 | Jim Perry | 41 | DET |
| +029+ | 1.35 | Gaylord Perry | 58 | CLE |
| +033+ | 1.31 | Carl Morton | 46 | ATL |
| +039+ | 1.26 | Ross Grimsley | 45.3 | CIN |
| XXXXX | 1.23 | Rogelio Moret | 14.7 | BOS |
| XXXXX | 1.13 | Nolan Ryan | 55 | ANA |
| XXXXX | 1.11 | Don Gullett | 53.7 | CIN |
| XXXXX | 1.04 | Harry Parker | 15.3 | NYN |
| XXXXX | 1 | Bob Gibson | 48 | SLN |
| XXXXX | 0.99 | Luke Walker | 12.3 | PIT |
| XXXXX | 0.95 | Ray Burris | 11.3 | CHN |
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