| Starter | Tm | Tier | Game |
|---|---|---|---|
| Orel Hershiser | LAN | 6.91 | 198908130_LAN_SFN |
| Bert Blyleven | ANA | 5.02 | 198908130_OAK_ANA |
| John Cerutti | TOR | 4.36 | 198908130_TOR_KCA |
| Bryn Smith | WAS | 3.44 | 198908150_SFN_WAS |
| Mike Scott | HOU | 3.41 | 198908150_PIT_HOU |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bobby Witt | TEX | -4.74 | 198908130_DET_TEX |
| Melido Perez | CHA | -2.82 | 198908130_CHA_SEA |
| Storm Davis | OAK | -1.7 | 198908150_CLE_OAK |
| Jim Clancy | HOU | -1.59 | 198908130_CIN_HOU |
| Andy Hawkins | NYA | -1.37 | 198908140_NYA_MIL |
Based on accumulated WAA for this season up to 1989-08-15.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +002+ | 6.16 | Chris Bosio | 190.3 | MIL |
| +006+ | 5.65 | Bert Blyleven | 179.3 | ANA |
| +007+ | 5.55 | Orel Hershiser | 191 | LAN |
| +008+ | 5.48 | Mike Moore | 174.3 | OAK |
| +009+ | 5.23 | Mark Langston | 192.3 | TOT |
| +010+ | 5.12 | Chuck Finley | 175.7 | ANA |
| +018+ | 4.53 | Bret Saberhagen | 175.7 | KCA |
| +022+ | 4.31 | John Cerutti | 160.7 | TOR |
| +023+ | 4.19 | Bryn Smith | 164.3 | WAS |
| +025+ | 4.11 | Ed Whitson | 179 | SDN |
| +027+ | 4.03 | John Smiley | 171.7 | PIT |
| +028+ | 3.89 | Greg Maddux | 177 | CHN |
| +030+ | 3.8 | Greg Swindell | 153.3 | CLE |
| +031+ | 3.79 | Mike Scott | 173.7 | HOU |
| +033+ | 3.72 | John Smoltz | 182.3 | ATL |
| +034+ | 3.68 | Kevin Brown | 170.7 | TEX |
| +043+ | 3.42 | Sid Fernandez | 153.7 | NYN |
| +048+ | 3.32 | Doug Drabek | 180.7 | PIT |
| +051+ | 3.15 | Mike Morgan | 135.7 | LAN |
| +055+ | 3.02 | Mike Bielecki | 154.7 | CHN |
| +059+ | 2.81 | Tom Candiotti | 151.7 | CLE |
| +061+ | 2.77 | Mark Gubicza | 208.7 | KCA |
| +060+ | 2.77 | Joe Magrane | 172.7 | SLN |
| +062+ | 2.75 | Dennis Martinez | 177 | WAS |
| +065+ | 2.73 | Todd Burns | 77.3 | OAK |
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