| Starter | Tm | Tier | Game |
|---|---|---|---|
| Chuck Finley | ANA | 6.93 | 199009180_DET_ANA |
| Ed Whitson | SDN | 6.77 | 199009180_SDN_HOU |
| Danny Darwin | HOU | 5.61 | 199009170_SDN_HOU |
| Norm Charlton | CIN | 3.38 | 199009160_LAN_CIN |
| Steve Farr | KCA | 2.28 | 199009170_KCA_MIN |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Jack Morris | DET | -4.03 | 199009180_DET_ANA |
| Steve Avery | ATL | -1.45 | 199009160_SDN_ATL |
| Mark Langston | ANA | -1.42 | 199009160_SEA_ANA |
| Melido Perez | CHA | -1.37 | 199009170_CHA_OAK |
| Jose Nunez | CHN | -0.94 | 199009160_CHN_SLN |
Based on accumulated WAA for this season up to 1990-09-18.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +005+ | 7.47 | Chuck Finley | 222 | ANA |
| +006+ | 7.21 | Ed Whitson | 218.7 | SDN |
| +007+ | 6.89 | Frank Viola | 222.3 | NYN |
| +010+ | 6.41 | Dave Stewart | 243 | OAK |
| +016+ | 5.71 | Danny Darwin | 149.7 | HOU |
| +018+ | 5.35 | Doug Drabek | 206 | PIT |
| +027+ | 4.62 | Steve Farr | 112.7 | KCA |
| +030+ | 4.5 | Norm Charlton | 135 | CIN |
| +033+ | 4.35 | Zane Smith | 192.3 | TOT |
| +034+ | 4.33 | Dave Stieb | 191 | TOR |
| +036+ | 4.06 | Oil Can Boyd | 180.3 | WAS |
| +039+ | 4.03 | Greg Hibbard | 194.3 | CHA |
| +040+ | 4.02 | Bob Welch | 216.3 | OAK |
| +041+ | 4 | Jose Rijo | 174 | CIN |
| +044+ | 3.92 | Ramon Martinez | 210.3 | LAN |
| +045+ | 3.75 | Kevin Appier | 160.7 | KCA |
| +048+ | 3.66 | Kirk McCaskill | 163 | ANA |
| +057+ | 3.38 | Tim Crews | 97.7 | LAN |
| +062+ | 3.14 | Bruce Hurst | 208.3 | SDN |
| +071+ | 2.82 | Greg Maddux | 217.7 | CHN |
| +075+ | 2.68 | Dave Wells | 168 | TOR |
| +090+ | 2.4 | Erik Hanson | 210.7 | SEA |
| +093+ | 2.38 | Randy Tomlin | 61.3 | PIT |
| +095+ | 2.35 | Charlie Leibrandt | 143.3 | ATL |
| +097+ | 2.29 | Mike Boddicker | 208.7 | BOS |
_