| Starter | Tm | Tier | Game |
|---|---|---|---|
| Wilbur Wood | CHA | 18.28 | 197305100_CHA_ANA |
| Gaylord Perry | CLE | 6.45 | 197305120_CLE_BOS |
| Jim Palmer | BAL | 6.31 | 197305110_BAL_NYA |
| Don Sutton | LAN | 6.27 | 197305120_LAN_SFN |
| Tom Seaver | NYN | 5 | 197305120_NYN_PIT |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Pete Broberg | TEX | -2.54 | 197305120_OAK_TEX |
| Sam McDowell | SFN | -2.21 | 197305100_SLN_SFN |
| Jerry Reuss | HOU | -1.85 | 197305120_CIN_HOU |
| Johnny Odom | OAK | -1.33 | 197305120_OAK_TEX |
| Brent Strom | CLE | -1.13 | 197305110_CLE_BOS |
Based on accumulated WAA for this season up to 1973-05-12.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +001+ | 4.3 | Wilbur Wood | 84.3 | CHA |
| +002+ | 3.64 | Ken Holtzman | 69.7 | OAK |
| +003+ | 3.33 | Tom Seaver | 65.3 | NYN |
| +005+ | 2.8 | Dave McNally | 67.3 | BAL |
| +008+ | 2.6 | Bill Singer | 61.7 | ANA |
| +009+ | 2.55 | Gaylord Perry | 76 | CLE |
| +012+ | 2.4 | Rick Reuschel | 51.3 | CHN |
| +013+ | 2.35 | Ron Bryant | 61.7 | SFN |
| +015+ | 2.34 | Bill Greif | 37 | SDN |
| +016+ | 2.08 | Jerry Koosman | 50.3 | NYN |
| +017+ | 1.98 | Jerry Reuss | 58.3 | HOU |
| +018+ | 1.98 | Jim Perry | 49 | DET |
| +025+ | 1.72 | Jim Palmer | 51.7 | BAL |
| +029+ | 1.5 | Ross Grimsley | 55.7 | CIN |
| +033+ | 1.42 | Al Downing | 43.3 | LAN |
| +035+ | 1.42 | Don Sutton | 64 | LAN |
| +036+ | 1.41 | Bruce DalCanton | 37 | KCA |
| +037+ | 1.39 | Paul Splittorff | 62 | KCA |
| +040+ | 1.34 | Joe Coleman | 59 | DET |
| +043+ | 1.31 | Rudy May | 36 | ANA |
| +045+ | 1.26 | Rogelio Moret | 14.7 | BOS |
| XXXXX | 1.22 | Jim Colborn | 39.3 | MIL |
| XXXXX | 1.2 | Jack Billingham | 59.7 | CIN |
| XXXXX | 1.13 | Roger Nelson | 33.7 | CIN |
| XXXXX | 1.09 | Juan Marichal | 54 | SFN |
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