| 1989-04-04 | vs ATL | 1 | W 10-3 | - | | 27,989 | Mike Scott | Zane Smith | Mike Scott | Zane Smith | | 10 | 3 | 7 |
| 1989-04-05 | vs ATL | 2 | L 4-8 | - | | 12,154 | Bob Knepper | Pete Smith | Jose Alvarez | Bob Knepper | Joe Boever | 14 | 11 | 3 |
| 1989-04-06 | vs ATL | 3 | L 2-3 | - | | 9,259 | Jim Deshaies | John Smoltz | John Smoltz | Jim Deshaies | Joe Boever | 16 | 14 | 2 |
| 1989-04-07 | vs SDN | 4 | L 3-5 | - | | 15,971 | Rick Rhoden | Dennis Rasmussen | Dennis Rasmussen | Rick Rhoden | Mark Davis | 19 | 19 | 0 |
| 1989-04-08 | vs SDN | 5 | W 6-2 | - | | 19,427 | Jim Clancy | Walt Terrell | Jim Clancy | Walt Terrell | | 25 | 21 | 4 |
| 1989-04-09 | vs SDN | 6 | L 4-5 | - | | 19,585 | Mike Scott | Eric Show | Eric Show | Mike Scott | Mark Davis | 29 | 26 | 3 |
| 1989-04-10 | vs CIN | 7 | L 3-8 | - | | 10,090 | Bob Knepper | Tom Browning | Tom Browning | Bob Knepper | Rob Dibble | 32 | 34 | -2 |
| 1989-04-11 | vs CIN | 8 | W 5-3 | - | | 22,490 | Jim Deshaies | Rick Mahler | Jim Deshaies | Rick Mahler | Dave Smith | 37 | 37 | 0 |
| 1989-04-12 | vs CIN | 9 | L 1-3 | - | | 9,723 | Rick Rhoden | Jose Rijo | Rob Dibble | Dave Smith | John Franco | 38 | 40 | -2 |
| 1989-04-13 | @ LAN | 10 | W 4-2 | - | | 47,136 | Jim Clancy | Tim Belcher | Bob Forsch | Ray Searage | | 42 | 42 | 0 |
| 1989-04-14 | @ LAN | 11 | W 3-2 | - | | 44,312 | Mike Scott | Mike Morgan | Mike Scott | Mike Morgan | | 45 | 44 | 1 |
| 1989-04-15 | @ LAN | 12 | L 1-3 | - | | 43,836 | Bob Knepper | Orel Hershiser | Orel Hershiser | Bob Knepper | Alejandro Pena | 46 | 47 | -1 |
| 1989-04-16 | @ LAN | 13 | L 1-2 | - | | 39,520 | Jim Deshaies | Tim Leary | Tim Leary | Jim Deshaies | | 47 | 49 | -2 |
| 1989-04-18 | @ ATL | 14 | L 4-5 | - | | 8,758 | Rick Rhoden | Tom Glavine | Joe Boever | Dave Smith | | 51 | 54 | -3 |
| 1989-04-19 | @ ATL | 15 | L 3-4 | - | | 6,292 | Jim Clancy | Derek Lilliquist | Jose Alvarez | Jim Clancy | Joe Boever | 54 | 58 | -4 |
| 1989-04-20 | @ ATL | 16 | W 4-3 | - | | 5,568 | Mike Scott | Zane Smith | Danny Darwin | Paul Assenmacher | Dave Smith | 58 | 61 | -3 |
| 1989-04-21 | @ CIN | 17 | W 7-0 | - | | 30,828 | Jim Deshaies | Rick Mahler | Jim Deshaies | Rick Mahler | | 65 | 61 | 4 |
| 1989-04-22 | @ CIN | 18 | L 4-5 | - | | 31,073 | Rick Rhoden | Jose Rijo | Tim Birtsas | Danny Darwin | | 69 | 66 | 3 |
| 1989-04-23 | @ CIN | 19 | W 5-2 | - | | 21,967 | Bob Knepper | Danny Jackson | Bob Knepper | Danny Jackson | Larry Andersen | 74 | 68 | 6 |
| 1989-04-24 | vs PHI | 20 | L 4-8 | - | | 9,088 | Jim Clancy | Marvin Freeman | Greg Harris | Bob Forsch | | 78 | 76 | 2 |
| 1989-04-25 | vs PHI | 21 | W 4-1 | - | | 12,584 | Mike Scott | Ken Howell | Mike Scott | Ken Howell | | 82 | 77 | 5 |
| 1989-04-26 | vs PHI | 22 | W 6-5 | - | | 11,195 | Jim Deshaies | Floyd Youmans | Danny Darwin | Jeff Parrett | Dave Smith | 88 | 82 | 6 |
| 1989-04-28 | vs NYN | 23 | L 3-7 | - | | 21,990 | Rick Rhoden | Sid Fernandez | Sid Fernandez | Rick Rhoden | Roger McDowell | 91 | 89 | 2 |
| 1989-04-29 | vs NYN | 24 | L 1-5 | - | | 29,853 | Bob Knepper | Ron Darling | Ron Darling | Bob Knepper | Randy Myers | 92 | 94 | -2 |
| 1989-04-30 | vs NYN | 25 | W 7-6 | - | | 33,838 | Mike Scott | David Cone | Mike Scott | David Cone | Dave Smith | 99 | 100 | -1 |
| 1989-05-02 | @ PHI | 26 | W 12-4 | - | | 15,832 | Jim Deshaies | Floyd Youmans | Jim Deshaies | Floyd Youmans | | 111 | 104 | 7 |
| 1989-05-03 | @ MON | 27 | L 5-6 | - | | 7,462 | Rick Rhoden | Kevin Gross | Tim Burke | Juan Agosto | | 116 | 110 | 6 |
| 1989-05-04 | @ MON | 28 | W 5-4 | - | | 11,701 | Bob Knepper | Dennis Martinez | Danny Darwin | Joe Hesketh | Dave Smith | 121 | 114 | 7 |
| 1989-05-06 | @ NYN | 29 | L 1-2 | - | | 35,505 | Jim Clancy | David Cone | David Cone | Jim Clancy | | 122 | 116 | 6 |
| 1989-05-07 | @ NYN | 30 | W 5-0 | - | | 47,591 | Jim Deshaies | Dwight Gooden | Jim Deshaies | Dwight Gooden | | 127 | 116 | 11 |
| 1989-05-08 | vs MON | 31 | L 1-4 | - | | 11,044 | Bob Knepper | Kevin Gross | Kevin Gross | Bob Knepper | | 128 | 120 | 8 |
| 1989-05-09 | vs MON | 32 | L 2-4 | - | | 10,665 | Mike Scott | Dennis Martinez | Dennis Martinez | Mike Scott | Tim Burke | 130 | 124 | 6 |
| 1989-05-10 | vs MON | 33 | L 1-10 | - | | 9,628 | Jim Clancy | Bryn Smith | Bryn Smith | Jim Clancy | | 131 | 134 | -3 |
| 1989-05-12 | @ CHN | 34 | W 3-1 | - | | 21,141 | Jim Deshaies | Rick Sutcliffe | Jim Deshaies | Rick Sutcliffe | | 134 | 135 | -1 |
| 1989-05-13 | @ CHN | 35 | W 1-0 | - | | 27,775 | Bob Knepper | Greg Maddux | Bob Knepper | Greg Maddux | Dave Smith | 135 | 135 | 0 |
| 1989-05-14 | @ CHN | 36 | W 5-1 | - | | 23,391 | Mike Scott | Paul Kilgus | Mike Scott | Paul Kilgus | | 140 | 136 | 4 |
| 1989-05-16 | vs SLN | 37 | W 8-7 | - | | 12,685 | Jim Clancy | Jose DeLeon | Dan Schatzeder | Cris Carpenter | | 148 | 143 | 5 |
| 1989-05-17 | vs SLN | 38 | W 3-2 | - | | 11,605 | Jim Deshaies | Joe Magrane | Larry Andersen | Joe Magrane | | 151 | 145 | 6 |
| 1989-05-18 | vs SLN | 39 | L 3-4 | - | | 17,124 | Bob Knepper | Don Heinkel | Ken Dayley | Larry Andersen | | 154 | 149 | 5 |
| 1989-05-19 | vs PIT | 40 | W 3-0 | - | | 21,413 | Mike Scott | Bob Walk | Mike Scott | Bob Walk | | 157 | 149 | 8 |
| 1989-05-20 | vs PIT | 41 | W 5-4 | - | | 20,595 | Bob Forsch | Doug Drabek | Juan Agosto | Bob Kipper | | 162 | 153 | 9 |
| 1989-05-21 | vs PIT | 42 | L 5-17 | - | | 18,942 | Jim Clancy | Neal Heaton | Neal Heaton | Jim Clancy | Brian Fisher | 167 | 170 | -3 |
| 1989-05-22 | vs CHN | 43 | L 3-5 | - | | 11,923 | Jim Deshaies | Rick Sutcliffe | Rick Sutcliffe | Jim Deshaies | Calvin Schiraldi | 170 | 175 | -5 |
| 1989-05-23 | vs CHN | 44 | L 4-5 | - | | 15,665 | Mike Scott | Scott Sanderson | Scott Sanderson | Mike Scott | Calvin Schiraldi | 174 | 180 | -6 |
| 1989-05-24 | vs CHN | 45 | L 1-3 | - | | 17,042 | Bob Knepper | Greg Maddux | Greg Maddux | Bob Knepper | Mitch Williams | 175 | 183 | -8 |
| 1989-05-26 | @ PIT | 46 | W 4-2 | - | | 26,637 | Jim Clancy | Neal Heaton | Jim Clancy | Neal Heaton | Dave Smith | 179 | 185 | -6 |
| 1989-05-27 | @ PIT | 47 | W 5-4 | - | | 22,359 | Jim Deshaies | Brian Fisher | Dan Schatzeder | Jeff Robinson | Dave Smith | 184 | 189 | -5 |
| 1989-05-28 | @ PIT | 48 | W 9-2 | - | | 25,776 | Mike Scott | John Smiley | Mike Scott | John Smiley | Juan Agosto | 193 | 191 | 2 |
| 1989-05-29 | @ SLN | 49 | W 3-2 | - | | 30,012 | Bob Knepper | Ken Hill | Bob Knepper | Ken Hill | Dave Smith | 196 | 193 | 3 |
| 1989-05-30 | @ SLN | 50 | W 8-4 | - | | 36,370 | Bob Forsch | Scott Terry | Danny Darwin | Scott Terry | | 204 | 197 | 7 |
| 1989-05-31 | @ SLN | 51 | W 4-3 | - | | 34,258 | Jim Clancy | Jose DeLeon | Dan Schatzeder | Cris Carpenter | Dave Smith | 208 | 200 | 8 |
| 1989-06-01 | vs LAN | 52 | W 7-2 | - | | 18,488 | Jim Deshaies | Mike Morgan | Jim Deshaies | Mike Morgan | | 215 | 202 | 13 |
| 1989-06-02 | vs LAN | 53 | W 1-0 | - | | 32,736 | Mike Scott | Fernando Valenzuela | Mike Scott | Fernando Valenzuela | | 216 | 202 | 14 |
| 1989-06-03 | vs LAN | 54 | W 5-4 | - | | 34,425 | Bob Knepper | Tim Leary | Jim Clancy | Jeff Hamilton | | 221 | 206 | 15 |
| 1989-06-04 | vs LAN | 55 | W 7-6 | - | | 30,311 | Bob Forsch | Tim Belcher | Mike Scott | Alejandro Pena | | 228 | 212 | 16 |
| 1989-06-05 | vs SDN | 56 | L 2-10 | - | | 18,238 | Mark Portugal | Ed Whitson | Ed Whitson | Mark Portugal | | 230 | 222 | 8 |
| 1989-06-06 | vs SDN | 57 | W 8-7 | - | | 13,473 | Jim Deshaies | Dennis Rasmussen | Dave Smith | Mark Davis | | 238 | 229 | 9 |
| 1989-06-07 | vs SDN | 58 | W 3-2 | - | | 17,199 | Mike Scott | Walt Terrell | Mike Scott | Walt Terrell | Dave Smith | 241 | 231 | 10 |
| 1989-06-08 | vs SDN | 59 | W 7-6 | - | | 13,518 | Bob Knepper | Eric Show | Danny Darwin | Mark Davis | | 248 | 237 | 11 |
| 1989-06-09 | vs ATL | 60 | W 6-5 | - | | 24,530 | Bob Forsch | Derek Lilliquist | Juan Agosto | Jose Alvarez | Danny Darwin | 254 | 242 | 12 |
| 1989-06-10 | vs ATL | 61 | W 1-0 | - | | 31,972 | Jim Clancy | John Smoltz | Jim Clancy | John Smoltz | Dave Smith | 255 | 242 | 13 |
| 1989-06-11 | vs ATL | 62 | W 10-6 | - | | 30,001 | Jim Deshaies | Tom Glavine | Jim Deshaies | Tom Glavine | Danny Darwin | 265 | 248 | 17 |
| 1989-06-13 | @ LAN | 63 | L 2-3 | - | | 29,073 | Mike Scott | Fernando Valenzuela | Fernando Valenzuela | Mike Scott | Jay Howell | 267 | 251 | 16 |
| 1989-06-14 | @ LAN | 64 | L 0-3 | - | | 30,430 | Bob Knepper | Orel Hershiser | Orel Hershiser | Bob Knepper | | 267 | 254 | 13 |
| 1989-06-15 | @ LAN | 65 | L 1-2 | - | | 42,782 | Bob Forsch | Tim Belcher | John Wetteland | Juan Agosto | | 268 | 256 | 12 |
| 1989-06-16 | @ SDN | 66 | W 3-1 | - | | 18,709 | Jim Clancy | Ed Whitson | Jim Clancy | Ed Whitson | Dave Smith | 271 | 257 | 14 |
| 1989-06-17 | @ SDN | 67 | L 1-2 | - | | 41,118 | Jim Deshaies | Dennis Rasmussen | Greg Harris | Danny Darwin | | 272 | 259 | 13 |
| 1989-06-18 | @ SDN | 68 | W 5-2 | - | | 25,363 | Mike Scott | Walt Terrell | Mike Scott | Walt Terrell | | 277 | 261 | 16 |
| 1989-06-19 | @ SFN | 69 | L 2-3 | - | | 22,386 | Bob Knepper | Don Robinson | Don Robinson | Bob Knepper | Steve Bedrosian | 279 | 264 | 15 |
| 1989-06-20 | @ SFN | 70 | L 0-4 | - | | 21,074 | Bob Forsch | Scott Garrelts | Scott Garrelts | Bob Forsch | Craig Lefferts | 279 | 268 | 11 |
| 1989-06-21 | @ SFN | 71 | L 0-2 | - | | 32,730 | Jim Clancy | Rick Reuschel | Rick Reuschel | Jim Clancy | Steve Bedrosian | 279 | 270 | 9 |
| 1989-06-23 | @ ATL | 72 | W 5-2 | - | | 12,614 | Jim Deshaies | Pete Smith | Danny Darwin | Paul Assenmacher | Dave Smith | 284 | 272 | 12 |
| 1989-06-24 | @ ATL | 73 | W 5-4 | - | | 27,944 | Mike Scott | Zane Smith | Mike Scott | Jose Alvarez | Dave Smith | 289 | 276 | 13 |
| 1989-06-25 | @ ATL | 74 | W 12-6 | - | | 15,698 | Bob Knepper | Derek Lilliquist | Dan Schatzeder | Jim Acker | Danny Darwin | 301 | 282 | 19 |
| 1989-06-26 | vs SFN | 75 | L 3-4 | - | | 11,616 | Bob Forsch | Rick Reuschel | Craig Lefferts | Juan Agosto | Steve Bedrosian | 304 | 286 | 18 |
| 1989-06-27 | vs SFN | 76 | W 7-5 | - | | 33,231 | Jim Clancy | Mike LaCoss | Danny Darwin | Steve Bedrosian | | 311 | 291 | 20 |
| 1989-06-28 | vs SFN | 77 | W 7-3 | - | | 29,817 | Jim Deshaies | Don Robinson | Jim Deshaies | Don Robinson | | 318 | 294 | 24 |
| 1989-06-29 | @ MON | 78 | W 8-3 | - | | 15,715 | Mike Scott | Kevin Gross | Mike Scott | Kevin Gross | | 326 | 297 | 29 |
| 1989-06-30 | @ MON | 79 | L 1-6 | - | | 20,345 | Bob Knepper | Dennis Martinez | Dennis Martinez | Bob Knepper | | 327 | 303 | 24 |
| 1989-07-01 | @ MON | 80 | W 4-1 | - | | 27,421 | Bob Forsch | Pascual Perez | Larry Andersen | Pascual Perez | Dave Smith | 331 | 304 | 27 |
| 1989-07-02 | @ MON | 81 | L 2-13 | - | | 37,651 | Jim Clancy | Bryn Smith | Bryn Smith | Jim Clancy | | 333 | 317 | 16 |
| 1989-07-03 | vs NYN | 82 | L 1-3 | - | | 40,786 | Jim Deshaies | David Cone | David Cone | Jim Deshaies | Randy Myers | 334 | 320 | 14 |
| 1989-07-04 | vs NYN | 83 | W 10-3 | - | | 33,444 | Mike Scott | Bob Ojeda | Mike Scott | Bob Ojeda | | 344 | 323 | 21 |
| 1989-07-05 | vs NYN | 84 | W 6-5 | - | | 24,675 | Bob Knepper | Ron Darling | Danny Darwin | Ron Darling | Dave Smith | 350 | 328 | 22 |
| 1989-07-07 | vs MON | 85 | L 8-11 | - | | 31,369 | Bob Forsch | Pascual Perez | Joe Hesketh | Juan Agosto | Zane Smith | 358 | 339 | 19 |
| 1989-07-08 | vs MON | 86 | W 3-2 | - | | 28,418 | Jim Deshaies | Bryn Smith | Danny Darwin | Andy McGaffigan | Dave Smith | 361 | 341 | 20 |
| 1989-07-09 | vs MON | 87 | L 1-6 | - | | 28,221 | Mike Scott | Mark Langston | Mark Langston | Mike Scott | | 362 | 347 | 15 |
| 1989-07-13 | @ PHI | 88 | L 4-11 | - | | 0 | Bob Knepper | Bruce Ruffin | Bruce Ruffin | Bob Knepper | Greg Harris | 366 | 358 | 8 |
| 1989-07-13 | @ PHI | 89 | W 3-0 | - | | 22,771 | Bob Forsch | Dennis Cook | Bob Forsch | Dennis Cook | Dave Smith | 369 | 358 | 11 |
| 1989-07-14 | @ PHI | 90 | L 2-4 | - | | 32,300 | Jim Clancy | Terry Mulholland | Jeff Parrett | Larry Andersen | | 371 | 362 | 9 |
| 1989-07-15 | @ PHI | 91 | W 9-6 | - | | 25,574 | Mark Portugal | Larry McWilliams | Mark Portugal | Larry McWilliams | | 380 | 368 | 12 |
| 1989-07-17 | @ NYN | 92 | W 6-0 | - | | 0 | Jim Deshaies | Ron Darling | Jim Deshaies | Ron Darling | | 386 | 368 | 18 |
| 1989-07-17 | @ NYN | 93 | W 12-3 | - | | 36,278 | Bob Knepper | David West | Bob Knepper | David West | Danny Darwin | 398 | 371 | 27 |
| 1989-07-18 | @ NYN | 94 | L 0-9 | - | | 35,664 | Bob Forsch | Sid Fernandez | Sid Fernandez | Bob Forsch | | 398 | 380 | 18 |
| 1989-07-19 | @ NYN | 95 | L 2-8 | - | | 35,511 | Jim Clancy | David Cone | David Cone | Jim Clancy | | 400 | 388 | 12 |
| 1989-07-21 | vs PHI | 96 | W 4-2 | - | | 25,501 | Mike Scott | Terry Mulholland | Mike Scott | Terry Mulholland | Dave Smith | 404 | 390 | 14 |
| 1989-07-22 | vs PHI | 97 | W 1-0 | - | | 0 | Jim Deshaies | Ken Howell | Jim Deshaies | Ken Howell | Dave Smith | 405 | 390 | 15 |
| 1989-07-22 | vs PHI | 98 | W 4-3 | - | | 35,803 | Mark Portugal | Larry McWilliams | Danny Darwin | Larry McWilliams | | 409 | 393 | 16 |
| 1989-07-23 | vs PHI | 99 | W 3-2 | - | | 20,222 | Bob Forsch | Bruce Ruffin | Bob Forsch | Bruce Ruffin | Larry Andersen | 412 | 395 | 17 |
| 1989-07-25 | vs LAN | 100 | L 0-6 | - | | 28,910 | Rick Rhoden | Tim Belcher | Tim Belcher | Rick Rhoden | | 412 | 401 | 11 |
| 1989-07-26 | vs LAN | 101 | W 6-2 | - | | 33,563 | Mike Scott | Fernando Valenzuela | Mike Scott | Fernando Valenzuela | | 418 | 403 | 15 |
| 1989-07-27 | vs LAN | 102 | L 5-7 | - | | 30,466 | Jim Deshaies | Ramon Martinez | Mike Morgan | Larry Andersen | Jay Howell | 423 | 410 | 13 |
| 1989-07-28 | vs SFN | 103 | L 2-3 | - | | 38,845 | Jim Clancy | Don Robinson | Don Robinson | Jim Clancy | | 425 | 413 | 12 |
| 1989-07-29 | vs SFN | 104 | W 8-1 | - | | 39,602 | Mark Portugal | Rick Reuschel | Mark Portugal | Rick Reuschel | | 433 | 414 | 19 |
| 1989-07-30 | vs SFN | 105 | W 6-2 | - | | 41,088 | Mike Scott | Mike LaCoss | Mike Scott | Mike LaCoss | | 439 | 416 | 23 |
| 1989-08-01 | @ CIN | 106 | W 5-0 | - | | 20,999 | Rick Rhoden | Tim Leary | Rick Rhoden | Tim Leary | | 444 | 416 | 28 |
| 1989-08-02 | @ CIN | 107 | L 2-5 | - | | 23,490 | Jim Deshaies | Ron Robinson | Ron Robinson | Jim Deshaies | John Franco | 446 | 421 | 25 |
| 1989-08-03 | @ CIN | 108 | L 2-18 | - | | 20,179 | Jim Clancy | Tom Browning | Tom Browning | Jim Clancy | | 448 | 439 | 9 |
| 1989-08-04 | @ SFN | 109 | L 2-4 | - | | 26,648 | Mark Portugal | Don Robinson | Don Robinson | Danny Darwin | | 450 | 443 | 7 |
| 1989-08-05 | @ SFN | 110 | L 0-7 | - | | 33,736 | Mike Scott | Mike LaCoss | Mike LaCoss | Mike Scott | | 450 | 450 | 0 |
| 1989-08-06 | @ SFN | 111 | W 3-2 | - | | 52,292 | Rick Rhoden | Bob Knepper | Juan Agosto | Craig Lefferts | Dave Smith | 453 | 452 | 1 |
| 1989-08-07 | @ SDN | 112 | L 2-5 | - | | 28,613 | Jim Deshaies | Bruce Hurst | Bruce Hurst | Jim Deshaies | | 455 | 457 | -2 |
| 1989-08-08 | @ SDN | 113 | W 12-3 | - | | 16,988 | Jim Clancy | Don Schulze | Jim Clancy | Don Schulze | | 467 | 460 | 7 |
| 1989-08-09 | @ SDN | 114 | L 1-2 | - | | 18,120 | Mark Portugal | Ed Whitson | Mark Davis | Dave Smith | | 468 | 462 | 6 |
| 1989-08-10 | @ SDN | 115 | L 3-13 | - | | 16,760 | Bob Forsch | Greg Harris | Greg Harris | Bob Forsch | | 471 | 475 | -4 |
| 1989-08-11 | vs CIN | 116 | L 1-6 | - | | 36,044 | Rick Rhoden | Tim Leary | Tim Leary | Rick Rhoden | Rob Dibble | 472 | 481 | -9 |
| 1989-08-12 | vs CIN | 117 | W 6-5 | - | | 33,792 | Jim Deshaies | Ron Robinson | Dave Smith | John Franco | | 478 | 486 | -8 |
| 1989-08-13 | vs CIN | 118 | L 0-5 | - | | 26,825 | Jim Clancy | Tom Browning | Tom Browning | Jim Clancy | | 478 | 491 | -13 |
| 1989-08-15 | vs PIT | 119 | W 3-2 | - | | 23,574 | Mike Scott | Rick Reed | Larry Andersen | Mike Smith | | 481 | 493 | -12 |
| 1989-08-16 | vs PIT | 120 | L 4-5 | - | | 17,317 | Rick Rhoden | John Smiley | Neal Heaton | Larry Andersen | Bill Landrum | 485 | 498 | -13 |
| 1989-08-17 | vs PIT | 121 | W 5-3 | - | | 25,325 | Jim Deshaies | Jeff Robinson | Jim Deshaies | Jeff Robinson | | 490 | 501 | -11 |
| 1989-08-18 | vs CHN | 122 | W 6-5 | - | | 31,987 | Jim Clancy | Scott Sanderson | Dave Smith | Calvin Schiraldi | | 496 | 506 | -10 |
| 1989-08-19 | vs CHN | 123 | W 8-4 | - | | 41,661 | Mark Portugal | Greg Maddux | Mark Portugal | Greg Maddux | | 504 | 510 | -6 |
| 1989-08-20 | vs CHN | 124 | W 8-4 | - | | 38,624 | Mike Scott | Mike Bielecki | Danny Darwin | Les Lancaster | | 512 | 514 | -2 |
| 1989-08-22 | @ PIT | 125 | L 1-4 | - | | 14,638 | Jim Deshaies | John Smiley | John Smiley | Jim Deshaies | | 513 | 518 | -5 |
| 1989-08-23 | @ PIT | 126 | L 1-6 | - | | 12,564 | Jim Clancy | Bob Walk | Bob Walk | Jim Clancy | | 514 | 524 | -10 |
| 1989-08-24 | @ PIT | 127 | L 2-3 | - | | 13,884 | Mark Portugal | Doug Drabek | Doug Bair | Juan Agosto | | 516 | 527 | -11 |
| 1989-08-25 | vs SLN | 128 | L 4-7 | - | | 25,148 | Mike Scott | Jose DeLeon | Jose DeLeon | Mike Scott | | 520 | 534 | -14 |
| 1989-08-26 | vs SLN | 129 | L 3-5 | - | | 31,301 | Rick Rhoden | Ken Hill | Ken Hill | Rick Rhoden | Todd Worrell | 523 | 539 | -16 |
| 1989-08-27 | vs SLN | 130 | W 6-3 | - | | 20,697 | Bob Forsch | Ted Power | Bob Forsch | Ted Power | Dave Smith | 529 | 542 | -13 |
| 1989-08-28 | @ CHN | 131 | L 1-6 | - | | 23,039 | Jose Cano | Greg Maddux | Greg Maddux | Jose Cano | | 530 | 548 | -18 |
| 1989-08-29 | @ CHN | 132 | L 9-10 | - | | 25,829 | Mark Portugal | Mike Bielecki | Paul Assenmacher | Dave Smith | | 539 | 558 | -19 |
| 1989-08-30 | @ CHN | 133 | W 8-4 | - | | 37,218 | Mike Scott | Rick Sutcliffe | Mike Scott | Rick Sutcliffe | | 547 | 562 | -15 |
| 1989-09-01 | @ SLN | 134 | W 6-3 | - | | 33,086 | Jim Deshaies | Ken Hill | Jim Deshaies | John Costello | | 553 | 565 | -12 |
| 1989-09-02 | @ SLN | 135 | L 5-13 | - | | 47,580 | Bob Forsch | Ted Power | Ted Power | Bob Forsch | | 558 | 578 | -20 |
| 1989-09-03 | @ SLN | 136 | L 3-4 | - | | 41,181 | Mark Portugal | Joe Magrane | Todd Worrell | Danny Darwin | | 561 | 582 | -21 |
| 1989-09-04 | vs LAN | 137 | L 5-7 | - | | 19,058 | Mike Scott | John Wetteland | Mike Morgan | Mike Scott | Jay Howell | 566 | 589 | -23 |
| 1989-09-05 | vs LAN | 138 | W 3-2 | - | | 11,212 | Rick Rhoden | Ramon Martinez | Juan Agosto | Alejandro Pena | Larry Andersen | 569 | 591 | -22 |
| 1989-09-06 | vs SDN | 139 | L 2-3 | - | | 16,249 | Jim Deshaies | Calvin Schiraldi | Calvin Schiraldi | Jim Deshaies | Mark Davis | 571 | 594 | -23 |
| 1989-09-07 | vs SDN | 140 | W 2-1 | - | | 13,995 | Jim Clancy | Bruce Hurst | Jim Clancy | Bruce Hurst | Dave Smith | 573 | 595 | -22 |
| 1989-09-08 | vs SFN | 141 | W 5-2 | - | | 24,405 | Mark Portugal | Don Robinson | Mark Portugal | Don Robinson | Danny Darwin | 578 | 597 | -19 |
| 1989-09-09 | vs SFN | 142 | W 4-1 | - | | 37,711 | Mike Scott | Kelly Downs | Mike Scott | Kelly Downs | | 582 | 598 | -16 |
| 1989-09-10 | vs SFN | 143 | L 3-5 | - | | 26,004 | Rick Rhoden | Bob Knepper | Bob Knepper | Rick Rhoden | Craig Lefferts | 585 | 603 | -18 |
| 1989-09-11 | @ SDN | 144 | L 3-7 | - | | 12,705 | Jim Deshaies | Calvin Schiraldi | Calvin Schiraldi | Jim Deshaies | | 588 | 610 | -22 |
| 1989-09-12 | @ SDN | 145 | L 0-9 | - | | 16,509 | Jim Clancy | Bruce Hurst | Bruce Hurst | Jim Clancy | | 588 | 619 | -31 |
| 1989-09-13 | @ LAN | 146 | W 3-1 | - | | 21,715 | Mark Portugal | Orel Hershiser | Mark Portugal | Orel Hershiser | Danny Darwin | 591 | 620 | -29 |
| 1989-09-14 | @ LAN | 147 | W 11-3 | - | | 13,206 | Mike Scott | John Wetteland | Mike Scott | John Wetteland | | 602 | 623 | -21 |
| 1989-09-15 | vs CIN | 148 | W 4-1 | - | | 13,581 | Rick Rhoden | Jack Armstrong | Rick Rhoden | Jack Armstrong | Dave Smith | 606 | 624 | -18 |
| 1989-09-16 | vs CIN | 149 | W 3-1 | - | | 22,902 | Jim Deshaies | Ron Robinson | Jim Deshaies | Ron Robinson | | 609 | 625 | -16 |
| 1989-09-17 | vs CIN | 150 | W 1-0 | - | | 17,820 | Mark Portugal | Tom Browning | Mark Portugal | Tom Browning | | 610 | 625 | -15 |
| 1989-09-19 | @ ATL | 151 | L 0-3 | - | | 3,425 | Mike Scott | Gary Eave | Gary Eave | Mike Scott | Mike Stanton | 610 | 628 | -18 |
| 1989-09-20 | @ ATL | 152 | W 7-6 | - | | 2,794 | Rick Rhoden | Rusty Richards | Larry Andersen | Joe Boever | Brian Meyer | 617 | 634 | -17 |
| 1989-09-21 | @ ATL | 153 | L 0-3 | - | | 2,117 | Jim Deshaies | Tommy Greene | Tommy Greene | Jim Deshaies | | 617 | 637 | -20 |
| 1989-09-22 | @ SFN | 154 | W 3-1 | - | | 33,020 | Mark Portugal | Scott Garrelts | Mark Portugal | Scott Garrelts | Dan Schatzeder | 620 | 638 | -18 |
| 1989-09-23 | @ SFN | 155 | L 1-3 | - | | 46,664 | Mike Scott | Rick Reuschel | Rick Reuschel | Mike Scott | | 621 | 641 | -20 |
| 1989-09-24 | @ SFN | 156 | L 2-10 | - | | 50,871 | Jim Clancy | Mike LaCoss | Mike LaCoss | Jim Clancy | | 623 | 651 | -28 |
| 1989-09-25 | vs ATL | 157 | L 3-5 | - | | 18,547 | Jose Cano | Rusty Richards | Charlie Puleo | Dan Schatzeder | Mike Stanton | 626 | 656 | -30 |
| 1989-09-26 | vs ATL | 158 | W 3-2 | - | | 13,063 | Jim Deshaies | Tommy Greene | Jim Deshaies | Tommy Greene | Danny Darwin | 629 | 658 | -29 |
| 1989-09-27 | vs ATL | 159 | L 4-5 | - | | 12,338 | Mark Portugal | Kent Mercker | Mark Eichhorn | Jim Clancy | Mike Stanton | 633 | 663 | -30 |
| 1989-09-29 | @ CIN | 160 | L 3-4 | - | | 17,342 | Rick Rhoden | Tom Browning | Rob Dibble | Brian Meyer | John Franco | 636 | 667 | -31 |
| 1989-09-30 | @ CIN | 161 | W 9-2 | - | | 16,167 | Jose Cano | Scott Scudder | Jose Cano | Scott Scudder | | 645 | 669 | -24 |
| 1989-10-01 | @ CIN | 162 | W 2-0 | - | | 20,313 | Jim Deshaies | Tim Leary | Jim Deshaies | Tim Leary | | 647 | 669 | -22 |