| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bret Saberhagen | KCA | 8.65 | 198909221_SEA_KCA |
| Orel Hershiser | LAN | 6.29 | 198909240_SDN_LAN |
| Mike Moore | OAK | 5.31 | 198909230_OAK_MIN |
| Scott Garrelts | SFN | 4.73 | 198909220_HOU_SFN |
| Bert Blyleven | ANA | 4.01 | 198909232_ANA_CLE |
| Starter | Tm | Tier | Game |
|---|---|---|---|
| Bobby Witt | TEX | -5.72 | 198909230_CHA_TEX |
| Walt Terrell | NYA | -3.3 | 198909220_NYA_BAL |
| Jim Clancy | HOU | -2.11 | 198909240_HOU_SFN |
| Don August | MIL | -2.08 | 198909230_TOR_MIL |
| Mike Witt | ANA | -1.91 | 198909231_ANA_CLE |
Based on accumulated WAA for this season up to 1989-09-24.
| Rank | WAA | Name | IP | Tm |
|---|---|---|---|---|
| +002+ | 8.55 | Bret Saberhagen | 246 | KCA |
| +005+ | 7.29 | Orel Hershiser | 246 | LAN |
| +010+ | 6.01 | Scott Garrelts | 186.7 | SFN |
| +012+ | 5.75 | Mike Moore | 235 | OAK |
| +015+ | 5.59 | Ed Whitson | 220 | SDN |
| +017+ | 5.31 | Mark Langston | 244.3 | TOT |
| +018+ | 5.28 | Bruce Hurst | 238.3 | SDN |
| +020+ | 5.19 | Chuck Finley | 193.3 | ANA |
| +023+ | 5.01 | Rick Reuschel | 204.3 | SFN |
| +028+ | 4.77 | Chris Bosio | 235 | MIL |
| +029+ | 4.76 | Bert Blyleven | 232 | ANA |
| +033+ | 4.6 | Bryn Smith | 203.7 | WAS |
| +038+ | 4.19 | Kirk McCaskill | 198.7 | ANA |
| +041+ | 4.14 | Mark Gubicza | 255.7 | KCA |
| +042+ | 4.12 | Jose DeLeon | 233 | SLN |
| +045+ | 4.03 | Doug Drabek | 236.3 | PIT |
| +047+ | 3.94 | Mike Morgan | 152.3 | LAN |
| +048+ | 3.92 | John Smiley | 205.3 | PIT |
| +050+ | 3.87 | Joe Magrane | 227.7 | SLN |
| +053+ | 3.85 | Greg Maddux | 230 | CHN |
| +056+ | 3.72 | Tim Belcher | 221.3 | LAN |
| +060+ | 3.53 | Todd Burns | 93.7 | OAK |
| +063+ | 3.45 | Sid Fernandez | 202 | NYN |
| +075+ | 3.07 | Roger Clemens | 237.7 | BOS |
| +074+ | 3.07 | John Cerutti | 204.3 | TOR |
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