| Starter | Tm | Tier | Game |
|---|---|---|---|
| Orel Hershiser | LAN | 6.58 | 198908180_LAN_NYN |
| Mark Langston | WAS | 5.61 | 198908160_SFN_WAS |
| Chris Bosio | MIL | 5.26 | 198908170_BOS_MIL |
| Mike Moore | OAK | 4.77 | 198908160_CLE_OAK |
| Bret Saberhagen | KCA | 4.42 | 198908160_KCA_CHA |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Melido Perez | CHA | -3.51 | 198908180_TEX_CHA |
| Wes Gardner | BOS | -2.97 | 198908170_BOS_MIL |
| Don Carman | PHI | -1.82 | 198908160_LAN_PHI |
| Jim Clancy | HOU | -1.78 | 198908180_CHN_HOU |
| Shane Rawley | MIN | -1.68 | 198908160_MIN_ANA |
Based on accumulated WAA for this season up to 1989-08-18.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +004+ | 5.96 | Chris Bosio | 197.7 | MIL |
| +005+ | 5.65 | Bert Blyleven | 179.3 | ANA |
| +006+ | 5.63 | Orel Hershiser | 199 | LAN |
| +008+ | 5.55 | Mike Moore | 180 | OAK |
| +009+ | 5.41 | Mark Langston | 199.3 | TOT |
| +012+ | 5.12 | Chuck Finley | 175.7 | ANA |
| +017+ | 4.58 | Rick Reuschel | 160 | SFN |
| +019+ | 4.51 | Bret Saberhagen | 182.7 | KCA |
| +024+ | 4.19 | John Smiley | 178.7 | PIT |
| +025+ | 4.18 | Bryn Smith | 164.3 | WAS |
| +026+ | 4.14 | Ed Whitson | 179 | SDN |
| +031+ | 3.9 | Greg Maddux | 177 | CHN |
| +033+ | 3.82 | Greg Swindell | 153.3 | CLE |
| +034+ | 3.77 | John Cerutti | 164 | TOR |
| +035+ | 3.76 | Mike Scott | 173.7 | HOU |
| +036+ | 3.74 | John Smoltz | 182.3 | ATL |
| +041+ | 3.5 | Mike Bielecki | 162.7 | CHN |
| +044+ | 3.47 | Mark Gubicza | 216.7 | KCA |
| +047+ | 3.42 | Sid Fernandez | 153.7 | NYN |
| +048+ | 3.33 | Bruce Hurst | 196.3 | SDN |
| +050+ | 3.31 | Doug Drabek | 180.7 | PIT |
| +052+ | 3.23 | Kevin Brown | 175 | TEX |
| +053+ | 3.17 | Mike Morgan | 135.7 | LAN |
| +063+ | 2.8 | Joe Magrane | 172.7 | SLN |
| +064+ | 2.79 | Jim Deshaies | 174.7 | HOU |
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