| 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 |
| John Smiley | PIT | 3.27 | 198909210_WAS_PIT |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bob Knepper | SFN | -3.21 | 198909200_LAN_SFN |
| Melido Perez | CHA | -3.08 | 198909200_CHA_KCA |
| Randy Johnson | SEA | -1.75 | 198909210_SEA_TEX |
| Andy Hawkins | NYA | -1.61 | 198909212_MIL_NYA |
| Jack Morris | DET | -1.47 | 198909190_DET_BAL |
Based on accumulated WAA for this season up to 1989-09-21.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +002+ | 7.96 | Bret Saberhagen | 239 | KCA |
| +005+ | 6.91 | Orel Hershiser | 239 | LAN |
| +009+ | 6.24 | Mike Moore | 228.7 | OAK |
| +011+ | 5.95 | Scott Garrelts | 178.7 | SFN |
| +015+ | 5.58 | Ed Whitson | 220 | SDN |
| +017+ | 5.39 | Bert Blyleven | 225 | ANA |
| +020+ | 5.29 | Chuck Finley | 187.3 | ANA |
| +021+ | 5.18 | Mark Langston | 240.7 | TOT |
| +022+ | 5.09 | Bruce Hurst | 231.3 | SDN |
| +025+ | 4.79 | Chris Bosio | 235 | MIL |
| +030+ | 4.58 | Bryn Smith | 203.7 | WAS |
| +032+ | 4.45 | Rick Reuschel | 195.3 | SFN |
| +038+ | 4.17 | Kirk McCaskill | 198.7 | ANA |
| +039+ | 4.15 | Mark Gubicza | 255.7 | KCA |
| +040+ | 4.14 | Doug Drabek | 230.7 | PIT |
| +041+ | 4.14 | Jose DeLeon | 233 | SLN |
| +047+ | 3.94 | Mike Morgan | 152.3 | LAN |
| +049+ | 3.9 | John Smiley | 205.3 | PIT |
| +052+ | 3.86 | Greg Maddux | 230 | CHN |
| +055+ | 3.62 | John Cerutti | 198.7 | TOR |
| +062+ | 3.46 | Sid Fernandez | 202 | NYN |
| +064+ | 3.38 | Todd Burns | 92 | OAK |
| +065+ | 3.29 | Joe Magrane | 220.7 | SLN |
| +069+ | 3.17 | Tim Belcher | 212.3 | LAN |
| +073+ | 3.08 | Roger Clemens | 237.7 | BOS |
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