| Starter | Tm | Tier | Game |
|---|---|---|---|
| Orel Hershiser | LAN | 6.76 | 198909190_LAN_SFN |
| Mike Moore | OAK | 4.38 | 198909190_OAK_CLE |
| Chuck Finley | ANA | 3.78 | 198909190_ANA_MIN |
| Ed Whitson | SDN | 3.58 | 198909200_SDN_CIN |
| Mark Gubicza | KCA | 3.19 | 198909200_CHA_KCA |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bob Knepper | SFN | -3.21 | 198909200_LAN_SFN |
| Melido Perez | CHA | -3.08 | 198909200_CHA_KCA |
| David West | MIN | -1.9 | 198909180_ANA_MIN |
| Bob Walk | PIT | -1.63 | 198909180_PHI_PIT |
| Jack Morris | DET | -1.47 | 198909190_DET_BAL |
Based on accumulated WAA for this season up to 1989-09-20.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +002+ | 7.93 | Bret Saberhagen | 239 | KCA |
| +005+ | 6.87 | Orel Hershiser | 239 | LAN |
| +008+ | 6.22 | Mike Moore | 228.7 | OAK |
| +011+ | 5.93 | Scott Garrelts | 178.7 | SFN |
| +015+ | 5.56 | Ed Whitson | 220 | SDN |
| +017+ | 5.47 | Bert Blyleven | 225 | ANA |
| +019+ | 5.35 | Chuck Finley | 187.3 | ANA |
| +021+ | 5.16 | Mark Langston | 240.7 | TOT |
| +022+ | 5.07 | Bruce Hurst | 231.3 | SDN |
| +023+ | 4.77 | Chris Bosio | 235 | MIL |
| +024+ | 4.77 | John Smiley | 201 | PIT |
| +030+ | 4.56 | Bryn Smith | 203.7 | WAS |
| +033+ | 4.43 | Rick Reuschel | 195.3 | SFN |
| +039+ | 4.13 | Mark Gubicza | 255.7 | KCA |
| +041+ | 4.12 | Jose DeLeon | 233 | SLN |
| +040+ | 4.12 | Doug Drabek | 230.7 | PIT |
| +049+ | 3.81 | Kirk McCaskill | 191.3 | ANA |
| +050+ | 3.77 | Mike Morgan | 150.7 | LAN |
| +054+ | 3.6 | John Cerutti | 198.7 | TOR |
| +062+ | 3.37 | Todd Burns | 92 | OAK |
| +064+ | 3.27 | Greg Maddux | 221 | CHN |
| +065+ | 3.26 | Joe Magrane | 220.7 | SLN |
| +069+ | 3.13 | Tim Belcher | 212.3 | LAN |
| +072+ | 3.05 | Roger Clemens | 237.7 | BOS |
| +075+ | 2.98 | Mike Scott | 224 | HOU |
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