| Starter | Tm | Tier | Game |
|---|---|---|---|
| Orel Hershiser | LAN | 6.99 | 198909080_LAN_SDN |
| Scott Garrelts | SFN | 4.45 | 198909060_SFN_ATL |
| Chris Bosio | MIL | 4.42 | 198909060_MIL_ANA |
| Mark Gubicza | KCA | 4.38 | 198909080_MIN_KCA |
| Bert Blyleven | ANA | 3.75 | 198909080_BOS_ANA |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bobby Witt | TEX | -5.24 | 198909072_BAL_TEX |
| Charlie Leibrandt | KCA | -2.86 | 198909060_KCA_DET |
| Walt Terrell | NYA | -2.64 | 198909060_NYA_SEA |
| Jim Clancy | HOU | -2.62 | 198909070_SDN_HOU |
| David West | MIN | -2.43 | 198909060_MIN_TEX |
Based on accumulated WAA for this season up to 1989-09-08.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +004+ | 7.07 | Orel Hershiser | 226 | LAN |
| +007+ | 6.33 | Bret Saberhagen | 215 | KCA |
| +008+ | 5.91 | Scott Garrelts | 164.7 | SFN |
| +010+ | 5.76 | Mark Gubicza | 244.7 | KCA |
| +012+ | 5.54 | Chris Bosio | 226 | MIL |
| +017+ | 5.33 | Mike Moore | 208 | OAK |
| +018+ | 5.16 | Bert Blyleven | 210 | ANA |
| +019+ | 5.15 | Chuck Finley | 176.3 | ANA |
| +026+ | 4.47 | Ed Whitson | 201.7 | SDN |
| +028+ | 4.41 | Mark Langston | 224.3 | TOT |
| +032+ | 4.29 | Rick Reuschel | 182.3 | SFN |
| +034+ | 4.15 | Sid Fernandez | 183 | NYN |
| +036+ | 3.99 | Bob Welch | 183 | OAK |
| +039+ | 3.88 | Bryn Smith | 190.7 | WAS |
| +040+ | 3.83 | John Smoltz | 209.7 | ATL |
| +041+ | 3.8 | Bruce Hurst | 213.3 | SDN |
| +042+ | 3.69 | John Cerutti | 185 | TOR |
| +043+ | 3.69 | Mike Morgan | 149.3 | LAN |
| +054+ | 3.41 | Joe Magrane | 208.3 | SLN |
| +055+ | 3.37 | Greg Maddux | 209.3 | CHN |
| +060+ | 3.27 | Jose DeLeon | 214 | SLN |
| +061+ | 3.26 | Kirk McCaskill | 176.3 | ANA |
| +062+ | 3.23 | Dennis Martinez | 207.7 | WAS |
| +066+ | 3.1 | Doug Drabek | 216.7 | PIT |
| +077+ | 2.85 | Todd Burns | 85.7 | OAK |
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