| 1989-04-04 | vs PIT | 1 | W 6-5 | 1-0 | 2 | 35,154 | Dennis Martinez | Bob Walk | Andy McGaffigan | Jeff Robinson | | 6 | 5 | 1 |
| 1989-04-05 | vs PIT | 2 | L 0-3 | 1-1 | 2 | 9,137 | Randy Johnson | Doug Drabek | Doug Drabek | Randy Johnson | | 6 | 8 | -2 |
| 1989-04-06 | vs PIT | 3 | W 3-2 | 2-1 | 1 | 8,722 | Pascual Perez | John Smiley | Tim Burke | John Smiley | Joe Hesketh | 9 | 10 | -1 |
| 1989-04-07 | vs NYN | 4 | W 7-3 | 3-1 | 1 | 17,263 | Kevin Gross | Ron Darling | Kevin Gross | Ron Darling | | 16 | 13 | 3 |
| 1989-04-08 | vs NYN | 5 | W 3-2 | 4-1 | 1 | 23,506 | Bryn Smith | David Cone | Gene Harris | David Cone | Tim Burke | 19 | 15 | 4 |
| 1989-04-09 | vs NYN | 6 | L 1-2 | 4-2 | 2 | 23,662 | Dennis Martinez | Dwight Gooden | Dwight Gooden | Andy McGaffigan | Randy Myers | 20 | 17 | 3 |
| 1989-04-10 | @ PHI | 7 | L 6-7 | 4-3 | 3 | 13,194 | Randy Johnson | Floyd Youmans | Steve Bedrosian | Gene Harris | | 26 | 24 | 2 |
| 1989-04-11 | @ PHI | 8 | L 2-6 | 4-4 | 3 | 14,429 | Pascual Perez | Steve Ontiveros | Steve Ontiveros | Pascual Perez | | 28 | 30 | -2 |
| 1989-04-12 | @ PHI | 9 | L 3-6 | 4-5 | 3 | 15,461 | Kevin Gross | Don Carman | Don Carman | Kevin Gross | Steve Bedrosian | 31 | 36 | -5 |
| 1989-04-14 | @ PIT | 10 | W 7-6 | 5-5 | 3 | 15,052 | Dennis Martinez | Bob Walk | Joe Hesketh | Scott Medvin | Andy McGaffigan | 38 | 42 | -4 |
| 1989-04-15 | @ PIT | 11 | L 4-6 | 5-6 | 3 | 9,658 | Randy Johnson | Mike Dunne | Mike Dunne | Randy Johnson | Jeff Robinson | 42 | 48 | -6 |
| 1989-04-16 | @ PIT | 12 | W 5-4 | 6-6 | 3 | 18,107 | Pascual Perez | Doug Drabek | Joe Hesketh | Jeff Robinson | Tim Burke | 47 | 52 | -5 |
| 1989-04-17 | vs CHN | 13 | W 2-1 | 7-6 | 3 | 8,847 | Kevin Gross | Greg Maddux | Kevin Gross | Greg Maddux | Tim Burke | 49 | 53 | -4 |
| 1989-04-18 | vs CHN | 14 | W 11-2 | 8-6 | 3 | 11,913 | Bryn Smith | Paul Kilgus | Bryn Smith | Paul Kilgus | | 60 | 55 | 5 |
| 1989-04-19 | vs CHN | 15 | W 3-2 | 9-6 | 2 | 9,014 | Dennis Martinez | Scott Sanderson | Dennis Martinez | Scott Sanderson | Tim Burke | 63 | 57 | 6 |
| 1989-04-20 | @ SLN | 16 | L 2-5 | 9-7 | 3 | 22,839 | Randy Johnson | Ken Hill | Ken Hill | Randy Johnson | Todd Worrell | 65 | 62 | 3 |
| 1989-04-21 | @ SLN | 17 | L 0-1 | 9-8 | 3 | 32,227 | Pascual Perez | Jose DeLeon | Jose DeLeon | Tim Burke | | 65 | 63 | 2 |
| 1989-04-22 | @ SLN | 18 | L 2-5 | 9-9 | 4 | 41,325 | Kevin Gross | Scott Terry | Scott Terry | Kevin Gross | | 67 | 68 | -1 |
| 1989-04-23 | @ SLN | 19 | W 9-3 | 10-9 | 3 | 44,956 | Bryn Smith | Cris Carpenter | Bryn Smith | Cris Carpenter | | 76 | 71 | 5 |
| 1989-04-25 | @ CIN | 20 | L 1-6 | 10-10 | 3 | 16,469 | Dennis Martinez | Tom Browning | Tom Browning | Dennis Martinez | | 77 | 77 | 0 |
| 1989-04-26 | @ CIN | 21 | L 5-6 | 10-11 | 4 | 19,336 | Pascual Perez | Rick Mahler | Rick Mahler | Pascual Perez | John Franco | 82 | 83 | -1 |
| 1989-04-28 | vs ATL | 22 | W 10-4 | 11-11 | 4 | 14,591 | Kevin Gross | John Smoltz | Kevin Gross | John Smoltz | | 92 | 87 | 5 |
| 1989-04-29 | vs ATL | 23 | W 9-7 | 12-11 | 3 | 14,261 | Bryn Smith | Tom Glavine | Joe Hesketh | Jim Acker | Tim Burke | 101 | 94 | 7 |
| 1989-04-30 | vs ATL | 24 | W 9-6 | 13-11 | 3 | 25,221 | Brian Holman | Derek Lilliquist | Brian Holman | Derek Lilliquist | Tim Burke | 110 | 100 | 10 |
| 1989-05-01 | vs CIN | 25 | L 6-19 | 13-12 | 4 | 8,602 | Pascual Perez | Rick Mahler | Rick Mahler | Pascual Perez | | 116 | 119 | -3 |
| 1989-05-02 | vs CIN | 26 | W 6-4 | 14-12 | 3 | 10,102 | Randy Johnson | Jack Armstrong | Tim Burke | Kent Tekulve | | 122 | 123 | -1 |
| 1989-05-03 | vs HOU | 27 | W 6-5 | 15-12 | 3 | 7,462 | Kevin Gross | Rick Rhoden | Tim Burke | Juan Agosto | | 128 | 128 | 0 |
| 1989-05-04 | vs HOU | 28 | L 4-5 | 15-13 | 4 | 11,701 | Dennis Martinez | Bob Knepper | Danny Darwin | Joe Hesketh | Dave Smith | 132 | 133 | -1 |
| 1989-05-05 | @ ATL | 29 | L 1-6 | 15-14 | 4 | 6,104 | Bryn Smith | Derek Lilliquist | Derek Lilliquist | Bryn Smith | Jose Alvarez | 133 | 139 | -6 |
| 1989-05-06 | @ ATL | 30 | L 3-13 | 15-15 | 4 | 15,556 | Pascual Perez | Zane Smith | Zane Smith | Pascual Perez | | 136 | 152 | -16 |
| 1989-05-07 | @ ATL | 31 | L 1-7 | 15-16 | 4 | 14,278 | Randy Johnson | Pete Smith | Pete Smith | Randy Johnson | | 137 | 159 | -22 |
| 1989-05-08 | @ HOU | 32 | W 4-1 | 16-16 | 4 | 11,044 | Kevin Gross | Bob Knepper | Kevin Gross | Bob Knepper | | 141 | 160 | -19 |
| 1989-05-09 | @ HOU | 33 | W 4-2 | 17-16 | 4 | 10,665 | Dennis Martinez | Mike Scott | Dennis Martinez | Mike Scott | Tim Burke | 145 | 162 | -17 |
| 1989-05-10 | @ HOU | 34 | W 10-1 | 18-16 | 4 | 9,628 | Bryn Smith | Jim Clancy | Bryn Smith | Jim Clancy | | 155 | 163 | -8 |
| 1989-05-12 | vs SFN | 35 | L 1-2 | 18-17 | 4 | 15,851 | Pascual Perez | Rick Reuschel | Rick Reuschel | Pascual Perez | Rich Gossage | 156 | 165 | -9 |
| 1989-05-13 | vs SFN | 36 | W 5-4 | 19-17 | 3 | 13,029 | Kevin Gross | Don Robinson | Tim Burke | Atlee Hammaker | | 161 | 169 | -8 |
| 1989-05-14 | vs SFN | 37 | W 4-3 | 20-17 | 3 | 19,835 | Dennis Martinez | Mike Krukow | Dennis Martinez | Mike Krukow | Tim Burke | 165 | 172 | -7 |
| 1989-05-15 | vs SDN | 38 | L 5-6 | 20-18 | 3 | 12,110 | Bryn Smith | Walt Terrell | Mark Davis | Andy McGaffigan | | 170 | 178 | -8 |
| 1989-05-16 | vs SDN | 39 | L 2-5 | 20-19 | 4 | 12,508 | Brian Holman | Eric Show | Eric Show | Brian Holman | Greg Harris | 172 | 183 | -11 |
| 1989-05-17 | vs SDN | 40 | L 5-6 | 20-20 | 4 | 10,485 | Pascual Perez | Bruce Hurst | Mark Grant | Pascual Perez | Greg Harris | 177 | 189 | -12 |
| 1989-05-19 | vs LAN | 41 | L 0-8 | 20-21 | 4 | 16,197 | Kevin Gross | Tim Belcher | Tim Belcher | Kevin Gross | | 177 | 197 | -20 |
| 1989-05-20 | vs LAN | 42 | L 2-3 | 20-22 | 4 | 15,807 | Dennis Martinez | Orel Hershiser | Orel Hershiser | Pascual Perez | Jay Howell | 179 | 200 | -21 |
| 1989-05-21 | vs LAN | 43 | W 3-1 | 21-22 | 4 | 24,231 | Bryn Smith | Mike Morgan | Bryn Smith | Mike Morgan | | 182 | 201 | -19 |
| 1989-05-23 | @ SFN | 44 | L 2-4 | 21-23 | 4 | 13,018 | Brian Holman | Rick Reuschel | Rick Reuschel | Brian Holman | Mike LaCoss | 184 | 205 | -21 |
| 1989-05-24 | @ SFN | 45 | W 1-0 | 22-23 | 4 | 9,889 | Kevin Gross | Don Robinson | Kevin Gross | Don Robinson | | 185 | 205 | -20 |
| 1989-05-25 | @ SFN | 46 | W 2-0 | 23-23 | 4 | 14,125 | Dennis Martinez | Mike Krukow | Dennis Martinez | Mike Krukow | Tim Burke | 187 | 205 | -18 |
| 1989-05-26 | @ SDN | 47 | W 5-0 | 24-23 | 4 | 19,770 | Bryn Smith | Dennis Rasmussen | Bryn Smith | Dennis Rasmussen | | 192 | 205 | -13 |
| 1989-05-27 | @ SDN | 48 | L 0-5 | 24-24 | 4 | 37,999 | Mark Gardner | Walt Terrell | Walt Terrell | Mark Gardner | | 192 | 210 | -18 |
| 1989-05-28 | @ SDN | 49 | W 10-2 | 25-24 | 4 | 50,614 | Mark Langston | Eric Show | Mark Langston | Eric Show | | 202 | 212 | -10 |
| 1989-05-29 | @ LAN | 50 | W 3-2 | 26-24 | 2 | 44,953 | Kevin Gross | Tim Leary | Pascual Perez | Tim Leary | Tim Burke | 205 | 214 | -9 |
| 1989-05-30 | @ LAN | 51 | W 5-4 | 27-24 | 2 | 25,336 | Dennis Martinez | Tim Belcher | Joe Hesketh | Jay Howell | Tim Burke | 210 | 218 | -8 |
| 1989-05-31 | @ LAN | 52 | L 4-9 | 27-25 | 2 | 22,858 | Bryn Smith | Orel Hershiser | Orel Hershiser | Joe Hesketh | | 214 | 227 | -13 |
| 1989-06-02 | @ PHI | 53 | W 2-1 | 28-25 | 2 | 20,560 | Mark Langston | Ken Howell | Steve Frey | Greg Harris | Joe Hesketh | 216 | 228 | -12 |
| 1989-06-03 | @ PHI | 54 | W 7-5 | 29-25 | 2 | 35,269 | Kevin Gross | Larry McWilliams | Kevin Gross | Larry McWilliams | Tim Burke | 223 | 233 | -10 |
| 1989-06-04 | @ PHI | 55 | W 7-4 | 30-25 | 2 | 30,926 | Dennis Martinez | Floyd Youmans | Dennis Martinez | Don Carman | Andy McGaffigan | 230 | 237 | -7 |
| 1989-06-05 | vs SLN | 56 | L 4-5 | 30-26 | 2 | 17,261 | Bryn Smith | Jose DeLeon | Jose DeLeon | Bryn Smith | John Costello | 234 | 242 | -8 |
| 1989-06-06 | vs SLN | 57 | W 3-2 | 31-26 | 2 | 16,435 | Pascual Perez | Joe Magrane | Pascual Perez | Joe Magrane | Tim Burke | 237 | 244 | -7 |
| 1989-06-07 | vs SLN | 58 | L 2-5 | 31-27 | 2 | 30,214 | Mark Langston | Ken Hill | Ken Hill | Mark Langston | Ken Dayley | 239 | 249 | -10 |
| 1989-06-08 | vs SLN | 59 | L 2-7 | 31-28 | 2 | 12,402 | Kevin Gross | Scott Terry | Frank DiPino | Kevin Gross | | 241 | 256 | -15 |
| 1989-06-09 | vs PHI | 60 | W 5-0 | 32-28 | 2 | 15,791 | Dennis Martinez | Floyd Youmans | Dennis Martinez | Floyd Youmans | | 246 | 256 | -10 |
| 1989-06-10 | vs PHI | 61 | W 9-1 | 33-28 | 2 | 23,981 | Bryn Smith | Bruce Ruffin | Bryn Smith | Bruce Ruffin | | 255 | 257 | -2 |
| 1989-06-11 | vs PHI | 62 | W 7-2 | 34-28 | 2 | 34,365 | Pascual Perez | Bob Sebra | Pascual Perez | Bob Sebra | | 262 | 259 | 3 |
| 1989-06-13 | @ SLN | 63 | W 2-0 | 35-28 | 2 | 35,828 | Mark Langston | Jose DeLeon | Mark Langston | Jose DeLeon | | 264 | 259 | 5 |
| 1989-06-14 | @ SLN | 64 | L 0-10 | 35-29 | 2 | 36,246 | Kevin Gross | Joe Magrane | Joe Magrane | Kevin Gross | | 264 | 269 | -5 |
| 1989-06-15 | @ SLN | 65 | L 3-4 | 35-30 | 2 | 26,698 | Dennis Martinez | Ken Hill | Todd Worrell | Andy McGaffigan | | 267 | 273 | -6 |
| 1989-06-16 | vs CHN | 66 | W 8-5 | 36-30 | 1 | 26,264 | Bryn Smith | Paul Kilgus | Bryn Smith | Paul Kilgus | Tim Burke | 275 | 278 | -3 |
| 1989-06-17 | vs CHN | 67 | L 2-3 | 36-31 | 2 | 35,095 | Pascual Perez | Rick Sutcliffe | Rick Sutcliffe | Pascual Perez | Mitch Williams | 277 | 281 | -4 |
| 1989-06-18 | vs CHN | 68 | L 4-5 | 36-32 | 2 | 35,968 | Mark Langston | Mike Bielecki | Mike Bielecki | Mark Langston | Mitch Williams | 281 | 286 | -5 |
| 1989-06-19 | @ NYN | 69 | L 3-5 | 36-33 | 3 | 40,064 | Kevin Gross | Dwight Gooden | Dwight Gooden | Kevin Gross | Rick Aguilera | 284 | 291 | -7 |
| 1989-06-20 | @ NYN | 70 | W 8-5 | 37-33 | 3 | 37,570 | Dennis Martinez | Sid Fernandez | Tim Burke | Rick Aguilera | | 292 | 296 | -4 |
| 1989-06-21 | @ NYN | 71 | L 0-2 | 37-34 | 4 | 30,458 | Bryn Smith | David Cone | David Cone | Bryn Smith | Randy Myers | 292 | 298 | -6 |
| 1989-06-23 | @ CHN | 72 | W 5-1 | 38-34 | 4 | 36,239 | Mark Langston | Mike Bielecki | Mark Langston | Mike Bielecki | Tim Burke | 297 | 299 | -2 |
| 1989-06-24 | @ CHN | 73 | W 5-0 | 39-34 | 3 | 36,068 | Kevin Gross | Paul Kilgus | Kevin Gross | Paul Kilgus | | 302 | 299 | 3 |
| 1989-06-25 | @ CHN | 74 | W 5-0 | 40-34 | 3 | 34,491 | Dennis Martinez | Scott Sanderson | Dennis Martinez | Scott Sanderson | | 307 | 299 | 8 |
| 1989-06-26 | vs NYN | 75 | W 5-1 | 41-34 | 1 | 27,395 | Pascual Perez | Dwight Gooden | Pascual Perez | Dwight Gooden | | 312 | 300 | 12 |
| 1989-06-27 | vs NYN | 76 | W 3-2 | 42-34 | 1 | 28,349 | Bryn Smith | David Cone | Steve Frey | Rick Aguilera | | 315 | 302 | 13 |
| 1989-06-28 | vs NYN | 77 | W 4-3 | 43-34 | 1 | 31,229 | Mark Langston | Bob Ojeda | Mark Langston | Bob Ojeda | Tim Burke | 319 | 305 | 14 |
| 1989-06-29 | vs HOU | 78 | L 3-8 | 43-35 | 1 | 15,715 | Kevin Gross | Mike Scott | Mike Scott | Kevin Gross | | 322 | 313 | 9 |
| 1989-06-30 | vs HOU | 79 | W 6-1 | 44-35 | 1 | 20,345 | Dennis Martinez | Bob Knepper | Dennis Martinez | Bob Knepper | | 328 | 314 | 14 |
| 1989-07-01 | vs HOU | 80 | L 1-4 | 44-36 | 1 | 27,421 | Pascual Perez | Bob Forsch | Larry Andersen | Pascual Perez | Dave Smith | 329 | 318 | 11 |
| 1989-07-02 | vs HOU | 81 | W 13-2 | 45-36 | 1 | 37,651 | Bryn Smith | Jim Clancy | Bryn Smith | Jim Clancy | | 342 | 320 | 22 |
| 1989-07-03 | @ ATL | 82 | W 3-0 | 46-36 | 1 | 10,555 | Mark Langston | Tom Glavine | Mark Langston | Tom Glavine | | 345 | 320 | 25 |
| 1989-07-04 | @ ATL | 83 | L 3-9 | 46-37 | 1 | 27,245 | Kevin Gross | Marty Clary | Marty Clary | Kevin Gross | | 348 | 329 | 19 |
| 1989-07-05 | @ ATL | 84 | W 7-5 | 47-37 | 1 | 50,091 | Dennis Martinez | Derek Lilliquist | Dennis Martinez | Mark Eichhorn | Tim Burke | 355 | 334 | 21 |
| 1989-07-07 | @ HOU | 85 | W 11-8 | 48-37 | 1 | 31,369 | Pascual Perez | Bob Forsch | Joe Hesketh | Juan Agosto | Zane Smith | 366 | 342 | 24 |
| 1989-07-08 | @ HOU | 86 | L 2-3 | 48-38 | 1 | 28,418 | Bryn Smith | Jim Deshaies | Danny Darwin | Andy McGaffigan | Dave Smith | 368 | 345 | 23 |
| 1989-07-09 | @ HOU | 87 | W 6-1 | 49-38 | 1 | 28,221 | Mark Langston | Mike Scott | Mark Langston | Mike Scott | | 374 | 346 | 28 |
| 1989-07-13 | @ CIN | 88 | W 6-3 | 50-38 | 1 | 25,483 | Dennis Martinez | Danny Jackson | Dennis Martinez | Kent Tekulve | Tim Burke | 380 | 349 | 31 |
| 1989-07-14 | @ CIN | 89 | W 1-0 | 51-38 | 1 | 29,494 | Bryn Smith | Tom Browning | Bryn Smith | Tom Browning | Joe Hesketh | 381 | 349 | 32 |
| 1989-07-15 | @ CIN | 90 | L 3-5 | 51-39 | 1 | 34,997 | Mark Langston | Rick Mahler | Rick Mahler | Mark Langston | John Franco | 384 | 354 | 30 |
| 1989-07-16 | @ CIN | 91 | W 6-3 | 52-39 | 1 | 28,348 | Kevin Gross | Jose Rijo | Steve Frey | Kent Tekulve | Tim Burke | 390 | 357 | 33 |
| 1989-07-17 | vs ATL | 92 | W 5-2 | 53-39 | 1 | 35,110 | Pascual Perez | Tom Glavine | Pascual Perez | Tom Glavine | Tim Burke | 395 | 359 | 36 |
| 1989-07-18 | vs ATL | 93 | L 6-7 | 53-40 | 1 | 26,259 | Dennis Martinez | Pete Smith | Mark Eichhorn | Steve Frey | Joe Boever | 401 | 366 | 35 |
| 1989-07-19 | vs ATL | 94 | L 2-3 | 53-41 | 1 | 20,222 | Bryn Smith | John Smoltz | Mark Eichhorn | Joe Hesketh | Joe Boever | 403 | 369 | 34 |
| 1989-07-20 | vs CIN | 95 | W 4-1 | 54-41 | 1 | 24,009 | Mark Langston | Rick Mahler | Mark Langston | Rick Mahler | | 407 | 370 | 37 |
| 1989-07-21 | vs CIN | 96 | W 3-1 | 55-41 | 1 | 23,587 | Kevin Gross | Tim Leary | Kevin Gross | Tim Leary | Tim Burke | 410 | 371 | 39 |
| 1989-07-22 | vs CIN | 97 | W 6-5 | 56-41 | 1 | 28,278 | Pascual Perez | Ron Robinson | Andy McGaffigan | John Franco | | 416 | 376 | 40 |
| 1989-07-23 | vs CIN | 98 | W 12-4 | 57-41 | 1 | 33,217 | Dennis Martinez | Danny Jackson | Dennis Martinez | Danny Jackson | | 428 | 380 | 48 |
| 1989-07-24 | vs PHI | 99 | W 4-3 | 58-41 | 1 | 25,218 | Bryn Smith | Dennis Cook | Andy McGaffigan | Greg Harris | | 432 | 383 | 49 |
| 1989-07-25 | vs PHI | 100 | W 2-0 | 59-41 | 1 | 30,103 | Mark Langston | Don Carman | Mark Langston | Don Carman | | 434 | 383 | 51 |
| 1989-07-26 | vs PHI | 101 | L 3-4 | 59-42 | 1 | 24,377 | Kevin Gross | Terry Mulholland | Jeff Parrett | Zane Smith | Roger McDowell | 437 | 387 | 50 |
| 1989-07-28 | vs SLN | 102 | L 0-2 | 59-43 | 1 | 41,722 | Pascual Perez | Ted Power | Ted Power | Pascual Perez | Todd Worrell | 437 | 389 | 48 |
| 1989-07-29 | vs SLN | 103 | W 2-0 | 60-43 | 1 | 33,886 | Dennis Martinez | Ken Hill | Dennis Martinez | Ken Hill | | 439 | 389 | 50 |
| 1989-07-30 | vs SLN | 104 | L 3-8 | 60-44 | 1 | 42,591 | Bryn Smith | Joe Magrane | Joe Magrane | Bryn Smith | | 442 | 397 | 45 |
| 1989-07-31 | @ PIT | 105 | W 4-2 | 61-44 | 1 | 13,150 | Mark Langston | John Smiley | Mark Langston | John Smiley | Tim Burke | 446 | 399 | 47 |
| 1989-08-01 | @ PIT | 106 | W 5-4 | 62-44 | 1 | 14,912 | Kevin Gross | Jeff Robinson | Tim Burke | Doug Bair | | 451 | 403 | 48 |
| 1989-08-02 | @ PIT | 107 | W 3-1 | 63-44 | 1 | 27,645 | Pascual Perez | Rick Reed | Pascual Perez | Rick Reed | Tim Burke | 454 | 404 | 50 |
| 1989-08-03 | @ PIT | 108 | L 0-1 | 63-45 | 1 | 12,292 | Dennis Martinez | Bob Walk | Doug Bair | Andy McGaffigan | | 454 | 405 | 49 |
| 1989-08-04 | @ NYN | 109 | L 5-11 | 63-46 | 1 | 41,457 | Bryn Smith | Bob Ojeda | Bob Ojeda | Bryn Smith | | 459 | 416 | 43 |
| 1989-08-05 | @ NYN | 110 | L 2-3 | 63-47 | 2 | 46,175 | Mark Langston | Ron Darling | Ron Darling | Tim Burke | | 461 | 419 | 42 |
| 1989-08-06 | @ NYN | 111 | L 1-2 | 63-48 | 2 | 43,658 | Kevin Gross | Sid Fernandez | Jeff Musselman | Steve Frey | | 462 | 421 | 41 |
| 1989-08-07 | @ CHN | 112 | L 2-5 | 63-49 | 2 | 39,002 | Pascual Perez | Greg Maddux | Greg Maddux | Pascual Perez | | 464 | 426 | 38 |
| 1989-08-08 | @ CHN | 113 | L 2-4 | 63-50 | 2 | 38,126 | Dennis Martinez | Mike Bielecki | Mike Bielecki | Dennis Martinez | Les Lancaster | 466 | 430 | 36 |
| 1989-08-09 | @ CHN | 114 | L 0-3 | 63-51 | 2 | 39,009 | Bryn Smith | Rick Sutcliffe | Rick Sutcliffe | Bryn Smith | Mitch Williams | 466 | 433 | 33 |
| 1989-08-11 | vs PIT | 115 | W 4-1 | 64-51 | 2 | 30,123 | Mark Langston | John Smiley | Mark Langston | John Smiley | | 470 | 434 | 36 |
| 1989-08-12 | vs PIT | 116 | W 5-2 | 65-51 | 2 | 27,697 | Kevin Gross | Jeff Robinson | Kevin Gross | Jeff Robinson | Zane Smith | 475 | 436 | 39 |
| 1989-08-13 | vs PIT | 117 | L 4-6 | 65-52 | 2 | 38,576 | Pascual Perez | Bob Walk | Bob Walk | Pascual Perez | Bill Landrum | 479 | 442 | 37 |
| 1989-08-14 | vs PIT | 118 | L 1-6 | 65-53 | 2 | 18,838 | Dennis Martinez | Doug Drabek | Doug Drabek | Dennis Martinez | | 480 | 448 | 32 |
| 1989-08-15 | vs SFN | 119 | L 2-3 | 65-54 | 3 | 24,490 | Bryn Smith | Dave Dravecky | Dave Dravecky | Bryn Smith | Steve Bedrosian | 482 | 451 | 31 |
| 1989-08-16 | vs SFN | 120 | W 4-2 | 66-54 | 3 | 24,719 | Mark Langston | Mike LaCoss | Tim Burke | Steve Bedrosian | | 486 | 453 | 33 |
| 1989-08-17 | vs SFN | 121 | L 5-10 | 66-55 | 3 | 21,057 | Kevin Gross | Don Robinson | Bob Knepper | Joe Hesketh | | 491 | 463 | 28 |
| 1989-08-18 | vs SDN | 122 | W 5-2 | 67-55 | 3 | 20,807 | Pascual Perez | Andy Benes | Pascual Perez | Andy Benes | | 496 | 465 | 31 |
| 1989-08-19 | vs SDN | 123 | W 6-4 | 68-55 | 3 | 24,914 | Dennis Martinez | Greg Harris | Dennis Martinez | Greg Harris | Tim Burke | 502 | 469 | 33 |
| 1989-08-20 | vs SDN | 124 | L 2-5 | 68-56 | 3 | 39,377 | Bryn Smith | Ed Whitson | Ed Whitson | Bryn Smith | Mark Davis | 504 | 474 | 30 |
| 1989-08-21 | vs LAN | 125 | L 1-6 | 68-57 | 3 | 24,440 | Mark Langston | Tim Belcher | Tim Belcher | Mark Langston | | 505 | 480 | 25 |
| 1989-08-22 | vs LAN | 126 | W 4-2 | 69-57 | 3 | 23,810 | Kevin Gross | Fernando Valenzuela | Kevin Gross | Fernando Valenzuela | Tim Burke | 509 | 482 | 27 |
| 1989-08-23 | vs LAN | 127 | L 0-1 | 69-58 | 3 | 21,742 | Pascual Perez | Orel Hershiser | John Wetteland | Dennis Martinez | | 509 | 483 | 26 |
| 1989-08-25 | @ SFN | 128 | W 12-2 | 70-58 | 2 | 23,272 | Dennis Martinez | Kelly Downs | Dennis Martinez | Kelly Downs | | 521 | 485 | 36 |
| 1989-08-26 | @ SFN | 129 | L 3-8 | 70-59 | 3 | 29,527 | Mark Langston | Scott Garrelts | Scott Garrelts | Mark Langston | | 524 | 493 | 31 |
| 1989-08-27 | @ SFN | 130 | W 6-3 | 71-59 | 2 | 31,536 | Bryn Smith | Mike LaCoss | Bryn Smith | Mike LaCoss | Tim Burke | 530 | 496 | 34 |
| 1989-08-28 | @ SDN | 131 | L 4-9 | 71-60 | 3 | 13,932 | Kevin Gross | Andy Benes | Andy Benes | Kevin Gross | Mark Davis | 534 | 505 | 29 |
| 1989-08-29 | @ SDN | 132 | L 1-2 | 71-61 | 4 | 17,687 | Pascual Perez | Greg Harris | Mark Grant | Rich Thompson | | 535 | 507 | 28 |
| 1989-08-30 | @ SDN | 133 | W 5-1 | 72-61 | 4 | 16,557 | Dennis Martinez | Ed Whitson | Dennis Martinez | Ed Whitson | | 540 | 508 | 32 |
| 1989-09-01 | @ LAN | 134 | L 0-2 | 72-62 | 4 | 24,844 | Mark Langston | Tim Belcher | Tim Belcher | Mark Langston | | 540 | 510 | 30 |
| 1989-09-02 | @ LAN | 135 | L 3-4 | 72-63 | 4 | 30,580 | Bryn Smith | Fernando Valenzuela | Jay Howell | Tim Burke | | 543 | 514 | 29 |
| 1989-09-03 | @ LAN | 136 | W 4-0 | 73-63 | 3 | 37,011 | Kevin Gross | Orel Hershiser | Kevin Gross | Orel Hershiser | | 547 | 514 | 33 |
| 1989-09-04 | @ SLN | 137 | L 1-4 | 73-64 | 3 | 42,610 | Dennis Martinez | Jose DeLeon | Jose DeLeon | Dennis Martinez | Dan Quisenberry | 548 | 518 | 30 |
| 1989-09-05 | @ SLN | 138 | W 6-2 | 74-64 | 3 | 24,788 | Pascual Perez | Ken Hill | Pascual Perez | Ken Hill | | 554 | 520 | 34 |
| 1989-09-06 | vs PIT | 139 | W 11-6 | 75-64 | 3 | 17,330 | Mark Langston | Randy Kramer | Mark Langston | Randy Kramer | | 565 | 526 | 39 |
| 1989-09-07 | vs PIT | 140 | L 4-7 | 75-65 | 3 | 16,390 | Bryn Smith | Bob Walk | Bob Walk | John Candelaria | Bill Landrum | 569 | 533 | 36 |
| 1989-09-08 | vs PHI | 141 | L 3-4 | 75-66 | 4 | 18,151 | Kevin Gross | Jason Grimsley | Jason Grimsley | Kevin Gross | Roger McDowell | 572 | 537 | 35 |
| 1989-09-09 | vs PHI | 142 | W 6-5 | 76-66 | 3 | 22,981 | Dennis Martinez | Terry Mulholland | Tim Burke | Jeff Parrett | | 578 | 542 | 36 |
| 1989-09-10 | vs PHI | 143 | L 2-4 | 76-67 | 3 | 22,630 | Pascual Perez | Pat Combs | Pat Combs | Pascual Perez | Roger McDowell | 580 | 546 | 34 |
| 1989-09-11 | @ CHN | 144 | L 3-4 | 76-68 | 4 | 29,190 | Mark Langston | Greg Maddux | Greg Maddux | Mark Langston | Mitch Williams | 583 | 550 | 33 |
| 1989-09-12 | @ CHN | 145 | L 0-2 | 76-69 | 4 | 36,333 | Bryn Smith | Mike Bielecki | Mike Bielecki | Bryn Smith | | 583 | 552 | 31 |
| 1989-09-13 | @ CHN | 146 | L 1-3 | 76-70 | 4 | 34,870 | Kevin Gross | Scott Sanderson | Scott Sanderson | Kevin Gross | Les Lancaster | 584 | 555 | 29 |
| 1989-09-15 | vs NYN | 147 | L 0-5 | 76-71 | 4 | 24,545 | Dennis Martinez | David Cone | David Cone | Dennis Martinez | | 584 | 560 | 24 |
| 1989-09-16 | vs NYN | 148 | W 10-1 | 77-71 | 4 | 32,228 | Pascual Perez | Sid Fernandez | Pascual Perez | Sid Fernandez | | 594 | 561 | 33 |
| 1989-09-17 | vs NYN | 149 | W 1-0 | 78-71 | 4 | 32,811 | Mark Langston | Ron Darling | Mark Langston | Ron Darling | | 595 | 561 | 34 |
| 1989-09-18 | vs SLN | 150 | L 2-3 | 78-72 | 4 | 14,644 | Bryn Smith | Jose DeLeon | Jose DeLeon | Bryn Smith | Scott Terry | 597 | 564 | 33 |
| 1989-09-19 | vs SLN | 151 | L 0-5 | 78-73 | 4 | 8,740 | Mark Gardner | Bob Tewksbury | Bob Tewksbury | Mark Gardner | | 597 | 569 | 28 |
| 1989-09-20 | @ PIT | 152 | L 1-9 | 78-74 | 4 | 11,926 | Kevin Gross | Neal Heaton | Neal Heaton | Kevin Gross | | 598 | 578 | 20 |
| 1989-09-21 | @ PIT | 153 | W 6-5 | 79-74 | 4 | 6,753 | Dennis Martinez | John Smiley | Dennis Martinez | John Smiley | Tim Burke | 604 | 583 | 21 |
| 1989-09-22 | @ NYN | 154 | L 2-3 | 79-75 | 4 | 16,640 | Pascual Perez | Ron Darling | Ron Darling | John Candelaria | Randy Myers | 606 | 586 | 20 |
| 1989-09-23 | @ NYN | 155 | L 6-13 | 79-76 | 4 | 36,844 | Mark Langston | Frank Viola | Frank Viola | Mark Langston | | 612 | 599 | 13 |
| 1989-09-24 | @ NYN | 156 | W 6-5 | 80-76 | 4 | 36,769 | Mark Gardner | David Cone | Joe Hesketh | Julio Machado | Tim Burke | 618 | 604 | 14 |
| 1989-09-25 | vs CHN | 157 | W 4-3 | 81-76 | 4 | 10,305 | Bryn Smith | Rick Sutcliffe | Tim Burke | Scott Sanderson | | 622 | 607 | 15 |
| 1989-09-26 | vs CHN | 158 | L 2-3 | 81-77 | 4 | 11,615 | Dennis Martinez | Greg Maddux | Greg Maddux | Dennis Martinez | Mitch Williams | 624 | 610 | 14 |
| 1989-09-27 | vs CHN | 159 | L 2-7 | 81-78 | 4 | 12,442 | Rich Thompson | Mike Bielecki | Mike Bielecki | Rich Thompson | Jeff Pico | 626 | 617 | 9 |
| 1989-09-29 | @ PHI | 160 | L 0-2 | 81-79 | 4 | 15,771 | Mark Langston | Dennis Cook | Dennis Cook | Mark Langston | | 626 | 619 | 7 |
| 1989-09-30 | @ PHI | 161 | L 3-6 | 81-80 | 4 | 20,448 | Mark Gardner | Bruce Ruffin | Bruce Ruffin | Mark Gardner | Roger McDowell | 629 | 625 | 4 |
| 1989-10-01 | @ PHI | 162 | L 3-5 | 81-81 | 4 | 25,213 | Bryn Smith | Pat Combs | Pat Combs | Bryn Smith | Roger McDowell | 632 | 630 | 2 |