| Starter | Tm | Tier | Game |
|---|---|---|---|
| Frank Viola | NYN | 4.88 | 199005070_HOU_NYN |
| Ted Higuera | MIL | 4.25 | 199005060_MIN_MIL |
| Doug Drabek | PIT | 3.93 | 199005062_ATL_PIT |
| Dennis Martinez | WAS | 3.71 | 199005050_SFN_WAS |
| Bryn Smith | SLN | 3.45 | 199005060_CIN_SLN |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Jack Morris | DET | -4.72 | 199005070_DET_MIL |
| Jim Clancy | HOU | -3.83 | 199005070_HOU_NYN |
| Rich Dotson | KCA | -3.34 | 199005050_CHA_KCA |
| Curt Young | OAK | -2.92 | 199005060_BOS_OAK |
| Bobby Witt | TEX | -2.32 | 199005062_TEX_CLE |
Based on accumulated WAA for this season up to 1990-05-07.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +001+ | 2.7 | Frank Viola | 42.7 | NYN |
| +002+ | 2.24 | Mike Morgan | 38.7 | LAN |
| +003+ | 2.13 | Jack Armstrong | 33.3 | CIN |
| +004+ | 2.07 | Dave Stewart | 41 | OAK |
| +007+ | 1.95 | Bob Welch | 42 | OAK |
| +008+ | 1.89 | Bud Black | 43.7 | CLE |
| +009+ | 1.86 | Dennis Cook | 34.3 | PHI |
| +010+ | 1.81 | Ed Whitson | 41 | SDN |
| +012+ | 1.73 | Teddy Higuera | 33.3 | MIL |
| +014+ | 1.62 | Greg Maddux | 36.7 | CHN |
| +015+ | 1.58 | Chris Bosio | 38.7 | MIL |
| +016+ | 1.57 | Mark Gardner | 27.3 | WAS |
| +018+ | 1.55 | Dave Stieb | 37.7 | TOR |
| +017+ | 1.55 | John Tudor | 33.3 | SLN |
| +022+ | 1.48 | Doug Drabek | 37.3 | PIT |
| +029+ | 1.34 | Pete Smith | 28.3 | ATL |
| +037+ | 1.27 | Chuck Finley | 31 | ANA |
| +036+ | 1.27 | Dennis Martinez | 43 | WAS |
| +039+ | 1.25 | Bryn Smith | 41.7 | SLN |
| XXXXX | 1.2 | Jim Deshaies | 37.7 | HOU |
| XXXXX | 1.2 | Tom Gordon | 23 | KCA |
| XXXXX | 1.08 | Eric King | 29 | CHA |
| XXXXX | 1.01 | Mike LaCoss | 27.7 | SFN |
| XXXXX | 0.94 | Neal Heaton | 31.3 | PIT |
| XXXXX | 0.86 | Fernando Valenzuela | 35 | LAN |
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