| 1989-04-03 | @ CLE | 1 | L 1-2 | - | | 40,618 | Don August | Greg Swindell | Greg Swindell | Don August | Doug Jones | 1 | 2 | -1 |
| 1989-04-06 | @ CLE | 2 | W 3-0 | - | | 4,905 | Chris Bosio | Buddy Black | Chris Bosio | Buddy Black | | 4 | 2 | 2 |
| 1989-04-07 | @ DET | 3 | L 3-10 | - | | 51,473 | Bill Wegman | Doyle Alexander | Doyle Alexander | Bill Wegman | Guillermo Hernandez | 7 | 12 | -5 |
| 1989-04-08 | @ DET | 4 | W 5-2 | - | | 12,892 | Don August | Frank Tanana | Don August | Frank Tanana | Dan Plesac | 12 | 14 | -2 |
| 1989-04-10 | vs TEX | 5 | L 4-6 | - | | 54,301 | Chris Bosio | Charlie Hough | Jeff Russell | Chuck Crim | | 16 | 20 | -4 |
| 1989-04-12 | vs TEX | 6 | L 1-8 | - | | 7,590 | Bill Wegman | Nolan Ryan | Nolan Ryan | Bill Wegman | | 17 | 28 | -11 |
| 1989-04-13 | vs TEX | 7 | L 1-6 | - | | 7,266 | Don August | Bobby Witt | Bobby Witt | Don August | | 18 | 34 | -16 |
| 1989-04-14 | vs CLE | 8 | W 8-4 | - | | 9,533 | Mike Birkbeck | Greg Swindell | Mark Knudson | Joe Skalski | Dan Plesac | 26 | 38 | -12 |
| 1989-04-15 | vs CLE | 9 | W 5-1 | - | | 19,043 | Chris Bosio | Tom Candiotti | Chris Bosio | Tom Candiotti | Chuck Crim | 31 | 39 | -8 |
| 1989-04-16 | vs CLE | 10 | W 4-3 | - | | 18,547 | Bryan Clutterbuck | John Farrell | Chuck Crim | Keith Atherton | | 35 | 42 | -7 |
| 1989-04-17 | @ TEX | 11 | W 8-1 | - | | 38,274 | Bill Wegman | Nolan Ryan | Bill Wegman | Nolan Ryan | Dan Plesac | 43 | 43 | 0 |
| 1989-04-18 | @ TEX | 12 | L 2-6 | - | | 21,528 | Don August | Bobby Witt | Bobby Witt | Don August | | 45 | 49 | -4 |
| 1989-04-19 | @ TEX | 13 | L 1-5 | - | | 19,444 | Mike Birkbeck | Jamie Moyer | Jamie Moyer | Mike Birkbeck | Cecilio Guante | 46 | 54 | -8 |
| 1989-04-21 | vs DET | 14 | W 2-1 | - | | 11,767 | Chris Bosio | Jack Morris | Chris Bosio | Jack Morris | Dan Plesac | 48 | 55 | -7 |
| 1989-04-22 | vs DET | 15 | L 3-6 | - | | 22,237 | Bill Wegman | Charles Hudson | Frank Williams | Chuck Crim | | 51 | 61 | -10 |
| 1989-04-23 | vs DET | 16 | L 3-11 | - | | 21,854 | Don August | Jeff Robinson | Paul Gibson | Don August | Guillermo Hernandez | 54 | 72 | -18 |
| 1989-04-24 | vs MIN | 17 | W 5-4 | - | | 9,311 | Mike Birkbeck | Frank Viola | Dan Plesac | Jeff Reardon | | 59 | 76 | -17 |
| 1989-04-25 | vs MIN | 18 | W 10-4 | - | | 10,034 | Bryan Clutterbuck | Roy Smith | Bryan Clutterbuck | Roy Smith | | 69 | 80 | -11 |
| 1989-04-26 | vs MIN | 19 | W 12-0 | - | | 10,912 | Chris Bosio | Allan Anderson | Chris Bosio | Allan Anderson | | 81 | 80 | 1 |
| 1989-04-28 | @ KCA | 20 | L 1-8 | - | | 27,515 | Bill Wegman | Charlie Leibrandt | Charlie Leibrandt | Bill Wegman | | 82 | 88 | -6 |
| 1989-04-29 | @ KCA | 21 | L 3-4 | - | | 30,475 | Don August | Bret Saberhagen | Tom Gordon | Dan Plesac | | 85 | 92 | -7 |
| 1989-04-30 | @ KCA | 22 | L 0-2 | - | | 40,113 | Mike Birkbeck | Floyd Bannister | Floyd Bannister | Mike Birkbeck | Steve Farr | 85 | 94 | -9 |
| 1989-05-01 | @ CHA | 23 | L 0-6 | - | | 7,625 | Teddy Higuera | Jerry Reuss | Jerry Reuss | Teddy Higuera | | 85 | 100 | -15 |
| 1989-05-02 | @ CHA | 24 | L 1-6 | - | | 6,534 | Chris Bosio | Eric King | Eric King | Chris Bosio | | 86 | 106 | -20 |
| 1989-05-03 | @ MIN | 25 | W 7-2 | - | | 21,479 | Bill Wegman | Shane Rawley | Bill Wegman | Shane Rawley | Bill Krueger | 93 | 108 | -15 |
| 1989-05-04 | @ MIN | 26 | W 3-2 | - | | 27,037 | Don August | Frank Viola | Don August | Frank Viola | Dan Plesac | 96 | 110 | -14 |
| 1989-05-05 | vs KCA | 27 | L 4-5 | - | | 16,751 | Mike Birkbeck | Floyd Bannister | Jeff Montgomery | Mark Knudson | Steve Farr | 100 | 115 | -15 |
| 1989-05-06 | vs KCA | 28 | W 1-0 | - | | 29,692 | Bryan Clutterbuck | Mark Gubicza | Bill Krueger | Tom Gordon | | 101 | 115 | -14 |
| 1989-05-07 | vs KCA | 29 | W 8-2 | - | | 22,524 | Chris Bosio | Charlie Leibrandt | Chris Bosio | Charlie Leibrandt | Chuck Crim | 109 | 117 | -8 |
| 1989-05-09 | vs CHA | 30 | L 1-10 | - | | 9,475 | Bill Wegman | Shawn Hillegas | Shawn Hillegas | Bill Wegman | | 110 | 127 | -17 |
| 1989-05-10 | vs CHA | 31 | L 2-12 | - | | 16,172 | Teddy Higuera | Melido Perez | Melido Perez | Teddy Higuera | | 112 | 139 | -27 |
| 1989-05-12 | @ OAK | 32 | L 4-5 | - | | 30,743 | Mike Birkbeck | Storm Davis | Todd Burns | Dan Plesac | | 116 | 144 | -28 |
| 1989-05-13 | @ OAK | 33 | L 3-4 | - | | 33,053 | Chris Bosio | Bob Welch | Bob Welch | Chris Bosio | Dennis Eckersley | 119 | 148 | -29 |
| 1989-05-14 | @ OAK | 34 | W 2-1 | - | | 26,989 | Bryan Clutterbuck | Mike Moore | Chuck Crim | Mike Moore | Dan Plesac | 121 | 149 | -28 |
| 1989-05-15 | @ OAK | 35 | L 2-12 | - | | 25,974 | Don August | Dave Stewart | Dave Stewart | Don August | | 123 | 161 | -38 |
| 1989-05-16 | @ SEA | 36 | L 5-6 | - | | 9,651 | Teddy Higuera | Mark Langston | Michael Jackson | Bill Wegman | Mike Schooler | 128 | 167 | -39 |
| 1989-05-17 | @ SEA | 37 | W 9-6 | - | | 9,271 | Mike Birkbeck | Scott Bankhead | Chuck Crim | Scott Bankhead | Dan Plesac | 137 | 173 | -36 |
| 1989-05-18 | @ SEA | 38 | L 5-9 | - | | 9,416 | Chris Bosio | Bill Swift | Bill Swift | Chris Bosio | Mike Schooler | 142 | 182 | -40 |
| 1989-05-19 | @ CAL | 39 | L 1-3 | - | | 39,978 | Bryan Clutterbuck | Chuck Finley | Chuck Finley | Bryan Clutterbuck | | 143 | 185 | -42 |
| 1989-05-20 | @ CAL | 40 | W 5-3 | - | | 34,764 | Don August | Bert Blyleven | Don August | Bert Blyleven | Dan Plesac | 148 | 188 | -40 |
| 1989-05-21 | @ CAL | 41 | L 9-12 | - | | 35,122 | Bill Wegman | Kirk McCaskill | Dan Petry | Bill Wegman | | 157 | 200 | -43 |
| 1989-05-23 | vs OAK | 42 | W 9-1 | - | | 13,882 | Chris Bosio | Bob Welch | Chris Bosio | Bob Welch | | 166 | 201 | -35 |
| 1989-05-24 | vs OAK | 43 | L 2-6 | - | | 13,932 | Mike Birkbeck | Mike Moore | Mike Moore | Mike Birkbeck | | 168 | 207 | -39 |
| 1989-05-25 | vs OAK | 44 | W 4-1 | - | | 18,898 | Bryan Clutterbuck | Dave Stewart | Bryan Clutterbuck | Dave Stewart | Dan Plesac | 172 | 208 | -36 |
| 1989-05-26 | vs SEA | 45 | L 2-7 | - | | 16,561 | Don August | Luis DeLeon | Michael Jackson | Don August | | 174 | 215 | -41 |
| 1989-05-27 | vs SEA | 46 | W 3-2 | - | | 26,094 | Teddy Higuera | Scott Bankhead | Dan Plesac | Brian Holman | | 177 | 217 | -40 |
| 1989-05-28 | vs SEA | 47 | W 6-4 | - | | 30,959 | Chris Bosio | Bill Swift | Chuck Crim | Dennis Powell | Dan Plesac | 183 | 221 | -38 |
| 1989-05-29 | vs CAL | 48 | L 3-12 | - | | 15,762 | Mike Birkbeck | Bert Blyleven | Bert Blyleven | Mike Birkbeck | | 186 | 233 | -47 |
| 1989-05-30 | vs CAL | 49 | L 2-3 | - | | 8,012 | Bryan Clutterbuck | Jim Abbott | Jim Abbott | Bryan Clutterbuck | Bob McClure | 188 | 236 | -48 |
| 1989-05-31 | vs CAL | 50 | W 4-1 | - | | 14,129 | Don August | Mike Witt | Don August | Mike Witt | Dan Plesac | 192 | 237 | -45 |
| 1989-06-01 | vs NYA | 51 | W 5-0 | - | | 18,991 | Teddy Higuera | Dave LaPoint | Teddy Higuera | Dave LaPoint | Jay Aldrich | 197 | 237 | -40 |
| 1989-06-02 | vs NYA | 52 | L 2-3 | - | | 28,876 | Chris Bosio | Clay Parker | Dave Righetti | Chuck Crim | | 199 | 240 | -41 |
| 1989-06-03 | vs NYA | 53 | W 2-0 | - | | 47,387 | Bill Krueger | Richard Dotson | Bill Krueger | Richard Dotson | Dan Plesac | 201 | 240 | -39 |
| 1989-06-04 | vs NYA | 54 | L 9-12 | - | | 52,179 | Bryan Clutterbuck | Jimmy Jones | Jimmy Jones | Bryan Clutterbuck | Lee Guetterman | 210 | 252 | -42 |
| 1989-06-05 | @ TOR | 55 | W 5-3 | - | | 48,378 | Don August | Jimmy Key | Don August | Jimmy Key | Dan Plesac | 215 | 255 | -40 |
| 1989-06-06 | @ TOR | 56 | W 6-4 | - | | 45,520 | Teddy Higuera | Frank Wills | Jay Aldrich | Duane Ward | Chuck Crim | 221 | 259 | -38 |
| 1989-06-07 | @ TOR | 57 | L 2-4 | - | | 45,372 | Chris Bosio | John Cerutti | John Cerutti | Chris Bosio | | 223 | 263 | -40 |
| 1989-06-08 | @ BAL | 58 | W 6-2 | - | | 30,378 | Bill Krueger | Bob Milacki | Mark Knudson | Bob Milacki | | 229 | 265 | -36 |
| 1989-06-09 | @ BAL | 59 | L 1-7 | - | | 31,156 | Bryan Clutterbuck | Brian Holton | Mark Williamson | Bryan Clutterbuck | | 230 | 272 | -42 |
| 1989-06-10 | @ BAL | 60 | W 6-0 | - | | 44,294 | Don August | Jeff Ballard | Don August | Jeff Ballard | | 236 | 272 | -36 |
| 1989-06-11 | @ BAL | 61 | W 3-1 | - | | 44,993 | Teddy Higuera | Jay Tibbs | Chuck Crim | Kevin Hickey | Dan Plesac | 239 | 273 | -34 |
| 1989-06-13 | vs TOR | 62 | L 3-4 | - | | 15,469 | Chris Bosio | Frank Wills | Duane Ward | Dan Plesac | | 242 | 277 | -35 |
| 1989-06-14 | vs TOR | 63 | L 1-6 | - | | 14,808 | Bill Krueger | Dave Stieb | Dave Stieb | Bill Krueger | | 243 | 283 | -40 |
| 1989-06-15 | vs TOR | 64 | W 6-4 | - | | 16,964 | Bryan Clutterbuck | Jimmy Key | Tony Fossas | Jimmy Key | Dan Plesac | 249 | 287 | -38 |
| 1989-06-16 | @ MIN | 65 | W 8-6 | - | | 35,047 | Don August | Allan Anderson | Chuck Crim | Juan Berenguer | Dan Plesac | 257 | 293 | -36 |
| 1989-06-17 | @ MIN | 66 | L 3-7 | - | | 42,107 | Teddy Higuera | Roy Smith | Lee Tunnell | Mark Knudson | | 260 | 300 | -40 |
| 1989-06-18 | @ MIN | 67 | L 6-8 | - | | 38,075 | Chris Bosio | Frank Viola | Jeff Reardon | Chuck Crim | | 266 | 308 | -42 |
| 1989-06-19 | @ MIN | 68 | W 11-8 | - | | 27,154 | Bill Krueger | Francisco Oliveras | Bill Krueger | Francisco Oliveras | Dan Plesac | 277 | 316 | -39 |
| 1989-06-20 | vs KCA | 69 | L 2-8 | - | | 17,185 | Jaime Navarro | Charlie Leibrandt | Tom Gordon | Mark Knudson | | 279 | 324 | -45 |
| 1989-06-21 | vs KCA | 70 | L 0-6 | - | | 18,086 | Don August | Bret Saberhagen | Bret Saberhagen | Don August | | 279 | 330 | -51 |
| 1989-06-22 | vs KCA | 71 | W 3-2 | - | | 21,607 | Teddy Higuera | Luis Aquino | Chuck Crim | Steve Farr | | 282 | 332 | -50 |
| 1989-06-23 | vs CHA | 72 | W 17-5 | - | | 0 | Chris Bosio | Steve Rosenberg | Chris Bosio | Steve Rosenberg | | 299 | 337 | -38 |
| 1989-06-23 | vs CHA | 73 | L 4-6 | - | | 28,702 | Bryan Clutterbuck | Melido Perez | Melido Perez | Bryan Clutterbuck | Bobby Thigpen | 303 | 343 | -40 |
| 1989-06-24 | vs CHA | 74 | L 3-5 | - | | 52,021 | Bill Krueger | Bill Long | Bill Long | Bill Krueger | Bobby Thigpen | 306 | 348 | -42 |
| 1989-06-25 | vs CHA | 75 | W 3-1 | - | | 40,201 | Jaime Navarro | Jerry Reuss | Jaime Navarro | Jerry Reuss | Dan Plesac | 309 | 349 | -40 |
| 1989-06-27 | vs BOS | 76 | W 5-4 | - | | 17,541 | Don August | Roger Clemens | Don August | Roger Clemens | Dan Plesac | 314 | 353 | -39 |
| 1989-06-28 | vs BOS | 77 | W 12-5 | - | | 18,813 | Teddy Higuera | Mike Smithson | Teddy Higuera | Mike Smithson | | 326 | 358 | -32 |
| 1989-06-29 | vs BOS | 78 | L 1-2 | - | | 31,202 | Chris Bosio | John Dopson | John Dopson | Chris Bosio | Lee Smith | 327 | 360 | -33 |
| 1989-06-30 | @ NYA | 79 | L 3-4 | - | | 26,374 | Jaime Navarro | Andy Hawkins | Andy Hawkins | Chuck Crim | Dave Righetti | 330 | 364 | -34 |
| 1989-07-01 | @ NYA | 80 | L 1-5 | - | | 24,851 | Randy Veres | Clay Parker | Clay Parker | Randy Veres | | 331 | 369 | -38 |
| 1989-07-02 | @ NYA | 81 | W 10-2 | - | | 33,631 | Don August | Lance McCullers | Don August | Lance McCullers | | 341 | 371 | -30 |
| 1989-07-03 | @ NYA | 82 | W 8-5 | - | | 23,035 | Teddy Higuera | Dave Eiland | Teddy Higuera | Dave Eiland | Dan Plesac | 349 | 376 | -27 |
| 1989-07-04 | @ BOS | 83 | W 4-3 | - | | 26,120 | Chris Bosio | John Dopson | Chris Bosio | Joe Price | Dan Plesac | 353 | 379 | -26 |
| 1989-07-06 | @ BOS | 84 | L 4-5 | - | | 33,538 | Jaime Navarro | Mike Boddicker | Mike Boddicker | Jaime Navarro | Lee Smith | 357 | 384 | -27 |
| 1989-07-07 | vs BAL | 85 | W 6-4 | - | | 27,313 | Don August | Pete Harnisch | Don August | Pete Harnisch | Dan Plesac | 363 | 388 | -25 |
| 1989-07-08 | vs BAL | 86 | L 2-5 | - | | 42,237 | Teddy Higuera | Brian Holton | Brian Holton | Teddy Higuera | Gregg Olson | 365 | 393 | -28 |
| 1989-07-09 | vs BAL | 87 | W 7-2 | - | | 39,328 | Chris Bosio | Dave J. Schmidt | Chris Bosio | Dave J. Schmidt | | 372 | 395 | -23 |
| 1989-07-13 | @ CHA | 88 | L 4-5 | - | | 13,966 | Don August | Jerry Reuss | Bobby Thigpen | Tony Fossas | | 376 | 400 | -24 |
| 1989-07-14 | @ CHA | 89 | L 4-6 | - | | 14,437 | Chris Bosio | Greg Hibbard | Bill Long | Chris Bosio | Donn Pall | 380 | 406 | -26 |
| 1989-07-15 | @ CHA | 90 | L 1-2 | - | | 22,404 | Teddy Higuera | Melido Perez | Melido Perez | Teddy Higuera | Bobby Thigpen | 381 | 408 | -27 |
| 1989-07-16 | @ CHA | 91 | L 0-2 | - | | 19,379 | Jaime Navarro | Richard Dotson | Richard Dotson | Jaime Navarro | Bobby Thigpen | 381 | 410 | -29 |
| 1989-07-17 | @ KCA | 92 | L 2-3 | - | | 37,961 | Tom Filer | Tom Gordon | Tom Gordon | Tom Filer | Jeff Montgomery | 383 | 413 | -30 |
| 1989-07-18 | @ KCA | 93 | L 4-9 | - | | 28,358 | Don August | Mark Gubicza | Mark Gubicza | Don August | | 387 | 422 | -35 |
| 1989-07-19 | @ KCA | 94 | W 7-1 | - | | 29,132 | Chris Bosio | Charlie Leibrandt | Chris Bosio | Charlie Leibrandt | | 394 | 423 | -29 |
| 1989-07-21 | vs MIN | 95 | W 5-3 | - | | 40,417 | Teddy Higuera | Shane Rawley | Teddy Higuera | Shane Rawley | | 399 | 426 | -27 |
| 1989-07-22 | vs MIN | 96 | L 1-6 | - | | 52,908 | Jaime Navarro | Roy Smith | Roy Smith | Jaime Navarro | Jeff Reardon | 400 | 432 | -32 |
| 1989-07-23 | vs MIN | 97 | W 4-1 | - | | 34,663 | Tom Filer | Frank Viola | Tom Filer | Frank Viola | Dan Plesac | 404 | 433 | -29 |
| 1989-07-24 | vs DET | 98 | W 10-0 | - | | 17,981 | Chris Bosio | Jack Morris | Chris Bosio | Jack Morris | | 414 | 433 | -19 |
| 1989-07-25 | vs DET | 99 | L 2-7 | - | | 16,737 | Don August | Doyle Alexander | Doyle Alexander | Don August | | 416 | 440 | -24 |
| 1989-07-26 | vs DET | 100 | W 3-2 | - | | 23,957 | Teddy Higuera | Frank Tanana | Teddy Higuera | Ed Nunez | Dan Plesac | 419 | 442 | -23 |
| 1989-07-27 | vs DET | 101 | W 11-1 | - | | 30,451 | Jaime Navarro | Paul Gibson | Jaime Navarro | Paul Gibson | | 430 | 443 | -13 |
| 1989-07-28 | @ TEX | 102 | W 15-3 | - | | 27,105 | Tom Filer | Mike Jeffcoat | Tom Filer | Mike Jeffcoat | | 445 | 446 | -1 |
| 1989-07-29 | @ TEX | 103 | W 8-2 | - | | 37,867 | Chris Bosio | Bobby Witt | Chris Bosio | Bobby Witt | Chuck Crim | 453 | 448 | 5 |
| 1989-07-30 | @ TEX | 104 | L 3-9 | - | | 37,943 | Don August | Nolan Ryan | Nolan Ryan | Don August | | 456 | 457 | -1 |
| 1989-07-31 | vs CLE | 105 | W 6-1 | - | | 17,434 | Teddy Higuera | Scott Bailes | Teddy Higuera | Scott Bailes | Chuck Crim | 462 | 458 | 4 |
| 1989-08-01 | vs CLE | 106 | W 4-2 | - | | 22,396 | Jaime Navarro | Ed Wojna | Jaime Navarro | Doug Jones | Dan Plesac | 466 | 460 | 6 |
| 1989-08-02 | vs CLE | 107 | L 0-1 | - | | 25,813 | Chris Bosio | Tom Candiotti | Tom Candiotti | Chris Bosio | Jesse Orosco | 466 | 461 | 5 |
| 1989-08-04 | vs CAL | 108 | L 2-6 | - | | 27,596 | Jerry Reuss | Chuck Finley | Chuck Finley | Jerry Reuss | Willie Fraser | 468 | 467 | 1 |
| 1989-08-05 | vs CAL | 109 | W 5-2 | - | | 42,324 | Teddy Higuera | Mike Witt | Teddy Higuera | Mike Witt | | 473 | 469 | 4 |
| 1989-08-06 | vs CAL | 110 | L 0-6 | - | | 31,455 | Jaime Navarro | Jim Abbott | Jim Abbott | Jaime Navarro | | 473 | 475 | -2 |
| 1989-08-07 | @ DET | 111 | L 3-5 | - | | 0 | Chris Bosio | Kevin Ritz | Kevin Ritz | Tony Fossas | Mike Henneman | 476 | 480 | -4 |
| 1989-08-07 | @ DET | 112 | W 5-2 | - | | 18,577 | Tom Filer | Paul Gibson | Tom Filer | Paul Gibson | Dan Plesac | 481 | 482 | -1 |
| 1989-08-08 | @ DET | 113 | L 3-6 | - | | 16,503 | Don August | Jeff Robinson | Jeff Robinson | Don August | Guillermo Hernandez | 484 | 488 | -4 |
| 1989-08-09 | @ DET | 114 | W 6-1 | - | | 24,348 | Jerry Reuss | Jack Morris | Chuck Crim | Jack Morris | Dan Plesac | 490 | 489 | 1 |
| 1989-08-10 | @ CLE | 115 | W 10-3 | - | | 15,506 | Teddy Higuera | Buddy Black | Teddy Higuera | Buddy Black | | 500 | 492 | 8 |
| 1989-08-11 | @ CLE | 116 | L 0-5 | - | | 0 | Jaime Navarro | John Farrell | John Farrell | Jaime Navarro | | 500 | 497 | 3 |
| 1989-08-11 | @ CLE | 117 | W 8-7 | - | | 47,795 | Mark Knudson | Ed Wojna | Mark Knudson | Ed Wojna | Dan Plesac | 508 | 504 | 4 |
| 1989-08-12 | @ CLE | 118 | W 5-1 | - | | 21,325 | Chris Bosio | Scott Bailes | Chris Bosio | Scott Bailes | | 513 | 505 | 8 |
| 1989-08-13 | @ CLE | 119 | W 5-4 | - | | 22,344 | Tom Filer | Tom Candiotti | Dan Plesac | Doug Jones | | 518 | 509 | 9 |
| 1989-08-14 | vs NYA | 120 | W 5-4 | - | | 22,829 | Jeff Peterek | Andy Hawkins | Tony Fossas | Dave Righetti | | 523 | 513 | 10 |
| 1989-08-15 | vs NYA | 121 | W 1-0 | - | | 38,829 | Teddy Higuera | Clay Parker | Teddy Higuera | Clay Parker | | 524 | 513 | 11 |
| 1989-08-16 | vs NYA | 122 | W 5-1 | - | | 41,036 | Mark Knudson | Walt Terrell | Mark Knudson | Walt Terrell | Chuck Crim | 529 | 514 | 15 |
| 1989-08-17 | vs BOS | 123 | W 8-4 | - | | 33,978 | Chris Bosio | Wes Gardner | Chris Bosio | Wes Gardner | | 537 | 518 | 19 |
| 1989-08-18 | vs BOS | 124 | W 5-2 | - | | 42,215 | Tom Filer | Tom Bolton | Tom Filer | Tom Bolton | Bill Krueger | 542 | 520 | 22 |
| 1989-08-19 | vs BOS | 125 | L 1-3 | - | | 49,539 | Jeff Peterek | Mike Boddicker | Greg Harris | Mark Knudson | | 543 | 523 | 20 |
| 1989-08-20 | vs BOS | 126 | W 6-3 | - | | 45,579 | Teddy Higuera | Mike Smithson | Jaime Navarro | Mike Smithson | Tony Fossas | 549 | 526 | 23 |
| 1989-08-21 | @ BAL | 127 | L 0-5 | - | | 31,912 | Jerry Reuss | Jeff Ballard | Jeff Ballard | Jerry Reuss | | 549 | 531 | 18 |
| 1989-08-22 | @ BAL | 128 | L 2-4 | - | | 31,726 | Chris Bosio | Dave Johnson | Dave Johnson | Chris Bosio | | 551 | 535 | 16 |
| 1989-08-23 | @ BAL | 129 | L 1-3 | - | | 32,702 | Tom Filer | Bob Milacki | Bob Milacki | Tom Filer | Gregg Olson | 552 | 538 | 14 |
| 1989-08-25 | @ TOR | 130 | L 1-3 | - | | 49,457 | Jeff Peterek | Jimmy Key | Jimmy Key | Jeff Peterek | Tom Henke | 553 | 541 | 12 |
| 1989-08-26 | @ TOR | 131 | L 0-7 | - | | 49,507 | Teddy Higuera | Dave Stieb | Dave Stieb | Teddy Higuera | | 553 | 548 | 5 |
| 1989-08-27 | @ TOR | 132 | L 4-5 | - | | 49,312 | Chris Bosio | Todd Stottlemyre | Todd Stottlemyre | Chris Bosio | Duane Ward | 557 | 553 | 4 |
| 1989-08-28 | @ TOR | 133 | W 8-2 | - | | 49,219 | Tom Filer | John Cerutti | Tom Filer | John Cerutti | Bill Krueger | 565 | 555 | 10 |
| 1989-08-29 | vs SEA | 134 | L 3-5 | - | | 15,720 | Jaime Navarro | Erik Hanson | Erik Hanson | Jaime Navarro | Mike Schooler | 568 | 560 | 8 |
| 1989-08-30 | vs SEA | 135 | L 3-7 | - | | 13,938 | Jeff Peterek | Randy Johnson | Randy Johnson | Jeff Peterek | Michael Jackson | 571 | 567 | 4 |
| 1989-08-31 | vs SEA | 136 | W 6-1 | - | | 15,540 | Mark Knudson | Brian Holman | Mark Knudson | Brian Holman | | 577 | 568 | 9 |
| 1989-09-01 | vs OAK | 137 | W 6-5 | - | | 17,465 | Chris Bosio | Bob Welch | Chuck Crim | Todd Burns | | 583 | 573 | 10 |
| 1989-09-02 | vs OAK | 138 | L 2-7 | - | | 36,980 | Tom Filer | Dave Stewart | Dave Stewart | Tom Filer | | 585 | 580 | 5 |
| 1989-09-03 | vs OAK | 139 | L 0-5 | - | | 30,583 | Jaime Navarro | Storm Davis | Storm Davis | Jaime Navarro | Gene Nelson | 585 | 585 | 0 |
| 1989-09-05 | @ CAL | 140 | L 4-8 | - | | 22,951 | Mark Knudson | Kirk McCaskill | Kirk McCaskill | Mark Knudson | Willie Fraser | 589 | 593 | -4 |
| 1989-09-06 | @ CAL | 141 | W 7-4 | - | | 22,459 | Chris Bosio | Dan Petry | Chris Bosio | Dan Petry | Dan Plesac | 596 | 597 | -1 |
| 1989-09-07 | @ CAL | 142 | W 7-1 | - | | 24,012 | Tom Filer | Mike Witt | Tom Filer | Mike Witt | | 603 | 598 | 5 |
| 1989-09-08 | @ SEA | 143 | W 7-3 | - | | 11,214 | Jaime Navarro | Clint Zavaras | Jaime Navarro | Clint Zavaras | | 610 | 601 | 9 |
| 1989-09-09 | @ SEA | 144 | W 7-3 | - | | 11,179 | Jerry Reuss | Erik Hanson | Jerry Reuss | Erik Hanson | | 617 | 604 | 13 |
| 1989-09-10 | @ SEA | 145 | W 7-1 | - | | 8,888 | Mark Knudson | Randy Johnson | Mark Knudson | Randy Johnson | | 624 | 605 | 19 |
| 1989-09-12 | @ OAK | 146 | W 7-6 | - | | 23,862 | Chris Bosio | Bob Welch | Don August | Matt Young | Dan Plesac | 631 | 611 | 20 |
| 1989-09-13 | @ OAK | 147 | L 6-7 | - | | 21,246 | Tom Filer | Dave Stewart | Dennis Eckersley | Chuck Crim | | 637 | 618 | 19 |
| 1989-09-15 | vs TEX | 148 | W 6-2 | - | | 18,290 | Jaime Navarro | Jamie Moyer | Jaime Navarro | Jamie Moyer | | 643 | 620 | 23 |
| 1989-09-16 | vs TEX | 149 | W 5-3 | - | | 44,115 | Jerry Reuss | John Barfield | Don August | John Barfield | Dan Plesac | 648 | 623 | 25 |
| 1989-09-17 | vs TEX | 150 | L 2-4 | - | | 22,129 | Chris Bosio | Bobby Witt | Bobby Witt | Chris Bosio | Kenny Rogers | 650 | 627 | 23 |
| 1989-09-21 | @ NYA | 151 | W 14-1 | - | | 0 | Mark Knudson | Greg Cadaret | Mark Knudson | Greg Cadaret | | 664 | 628 | 36 |
| 1989-09-21 | @ NYA | 152 | L 4-5 | - | | 11,230 | Jaime Navarro | Andy Hawkins | Lee Guetterman | Dan Plesac | | 668 | 633 | 35 |
| 1989-09-22 | vs TOR | 153 | L 3-7 | - | | 15,569 | Jerry Reuss | Dave Stieb | Dave Stieb | Jerry Reuss | | 671 | 640 | 31 |
| 1989-09-23 | vs TOR | 154 | W 4-1 | - | | 24,640 | Don August | Todd Stottlemyre | Don August | Todd Stottlemyre | Dan Plesac | 675 | 641 | 34 |
| 1989-09-24 | vs TOR | 155 | W 8-3 | - | | 17,485 | Tom Filer | John Cerutti | Tom Filer | John Cerutti | Chuck Crim | 683 | 644 | 39 |
| 1989-09-25 | vs BAL | 156 | L 3-5 | - | | 12,284 | Teddy Higuera | Pete Harnisch | Pete Harnisch | Teddy Higuera | Gregg Olson | 686 | 649 | 37 |
| 1989-09-26 | vs BAL | 157 | W 7-3 | - | | 12,814 | Jaime Navarro | Dave Johnson | Jaime Navarro | Dave Johnson | | 693 | 652 | 41 |
| 1989-09-27 | vs BAL | 158 | L 0-4 | - | | 14,463 | Jerry Reuss | Bob Milacki | Bob Milacki | Jerry Reuss | | 693 | 656 | 37 |
| 1989-09-28 | @ BOS | 159 | L 6-12 | - | | 28,954 | Don August | Mike Boddicker | Mike Boddicker | Don August | | 699 | 668 | 31 |
| 1989-09-29 | @ BOS | 160 | L 4-5 | - | | 32,906 | Tom Filer | Oil Can Boyd | Lee Smith | Chuck Crim | | 703 | 673 | 30 |
| 1989-09-30 | @ BOS | 161 | W 3-1 | - | | 33,243 | Mark Knudson | Roger Clemens | Mark Knudson | Roger Clemens | Dan Plesac | 706 | 674 | 32 |
| 1989-10-01 | @ BOS | 162 | L 1-5 | - | | 33,027 | Jaime Navarro | John Dopson | John Dopson | Jaime Navarro | Dennis Lamp | 707 | 679 | 28 |