| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bret Saberhagen | KCA | 5.04 | 198908310_DET_KCA |
| Chris Bosio | MIL | 4.03 | 198909010_OAK_MIL |
| Scott Garrelts | SFN | 3.29 | 198909010_NYN_SFN |
| Bryn Smith | WAS | 3.04 | 198909020_WAS_LAN |
| Greg Maddux | CHN | 2.48 | 198909020_CHN_ATL |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bobby Witt | TEX | -4.18 | 198908310_TEX_MIN |
| Don Carman | PHI | -2.45 | 198908310_PHI_SDN |
| David West | MIN | -2.4 | 198908310_TEX_MIN |
| Walt Terrell | NYA | -2.03 | 198909010_ANA_NYA |
| Bob Forsch | HOU | -2 | 198909020_HOU_SLN |
Based on accumulated WAA for this season up to 1989-09-02.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +005+ | 6.53 | Orel Hershiser | 214 | LAN |
| +006+ | 6.2 | Bret Saberhagen | 207.7 | KCA |
| +009+ | 5.72 | Mike Moore | 201.3 | OAK |
| +010+ | 5.55 | Chris Bosio | 217.7 | MIL |
| +015+ | 5.25 | Scott Garrelts | 155.7 | SFN |
| +017+ | 5.11 | Bert Blyleven | 198.7 | ANA |
| +019+ | 5.06 | Chuck Finley | 176.3 | ANA |
| +021+ | 4.71 | John Smiley | 187.7 | PIT |
| +022+ | 4.7 | Ed Whitson | 198 | SDN |
| +025+ | 4.58 | Mark Gubicza | 232.7 | KCA |
| +026+ | 4.51 | Rick Reuschel | 176.3 | SFN |
| +028+ | 4.35 | Greg Maddux | 205 | CHN |
| +030+ | 4.23 | Bryn Smith | 186 | WAS |
| +031+ | 4.21 | Mark Langston | 218.3 | TOT |
| +032+ | 4.21 | Joe Magrane | 199.3 | SLN |
| +040+ | 3.71 | Sid Fernandez | 174 | NYN |
| +041+ | 3.69 | Bob Welch | 178 | OAK |
| +043+ | 3.62 | Bruce Hurst | 207.3 | SDN |
| +045+ | 3.6 | Doug Drabek | 204.3 | PIT |
| +044+ | 3.6 | Tom Candiotti | 170.7 | CLE |
| +046+ | 3.59 | John Cerutti | 180 | TOR |
| +049+ | 3.49 | Mike Morgan | 145.7 | LAN |
| +051+ | 3.45 | Dennis Martinez | 201.7 | WAS |
| +053+ | 3.43 | John Smoltz | 203.7 | ATL |
| +056+ | 3.37 | Tom Browning | 222.7 | CIN |
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