| Starter | Tm | Tier | Game |
|---|---|---|---|
| Orel Hershiser | LAN | 5.66 | 198908230_LAN_WAS |
| Mark Langston | WAS | 5.06 | 198908210_LAN_WAS |
| Chris Bosio | MIL | 4.33 | 198908220_MIL_BAL |
| Chuck Finley | ANA | 4.07 | 198908210_ANA_KCA |
| Rick Reuschel | SFN | 3.71 | 198908230_SFN_NYN |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bob Knepper | SFN | -4.69 | 198908220_SFN_NYN |
| Wes Gardner | BOS | -3.35 | 198908220_BOS_NYA |
| Jim Clancy | HOU | -2.4 | 198908230_HOU_PIT |
| Shane Rawley | MIN | -2 | 198908220_CHA_MIN |
| Jerry Reuss | MIL | -1.46 | 198908210_MIL_BAL |
Based on accumulated WAA for this season up to 1989-08-23.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +003+ | 6.19 | Mike Moore | 188 | OAK |
| +005+ | 6.16 | Chris Bosio | 205.7 | MIL |
| +007+ | 6.03 | Orel Hershiser | 206 | LAN |
| +009+ | 5.44 | Bert Blyleven | 186.7 | ANA |
| +010+ | 5.09 | Rick Reuschel | 166 | SFN |
| +013+ | 4.97 | Chuck Finley | 176.3 | ANA |
| +014+ | 4.93 | Mark Langston | 208 | TOT |
| +017+ | 4.74 | Bret Saberhagen | 190.7 | KCA |
| +018+ | 4.73 | John Smiley | 187.7 | PIT |
| +023+ | 4.55 | Scott Garrelts | 140.3 | SFN |
| +026+ | 4.5 | Ed Whitson | 185.7 | SDN |
| +028+ | 4.31 | Bryn Smith | 173 | WAS |
| +030+ | 3.95 | Mike Scott | 181 | HOU |
| +032+ | 3.79 | Greg Swindell | 153.3 | CLE |
| +033+ | 3.76 | John Smoltz | 190.3 | ATL |
| +034+ | 3.75 | Sid Fernandez | 160.3 | NYN |
| +038+ | 3.59 | Mark Gubicza | 218.7 | KCA |
| +046+ | 3.37 | Bruce Hurst | 199.3 | SDN |
| +049+ | 3.32 | Joe Magrane | 181.3 | SLN |
| +050+ | 3.29 | Kirk McCaskill | 159.3 | ANA |
| +051+ | 3.23 | Greg Maddux | 189 | CHN |
| +052+ | 3.18 | John Cerutti | 168 | TOR |
| +055+ | 3.17 | Mike Morgan | 139.7 | LAN |
| +057+ | 3.13 | Mike Bielecki | 168.3 | CHN |
| +059+ | 3.08 | Tom Gordon | 125.3 | KCA |
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