| 1990-04-09 | vs SEA | 1 | L 4-7 | 0-1 | 7 | 38,406 | Bert Blyleven | Brian Holman | Brian Holman | Bert Blyleven | Mike Schooler | 4 | 7 | -3 |
| 1990-04-10 | vs SEA | 2 | W 7-0 | 1-1 | 5 | 23,508 | Chuck Finley | Randy Johnson | Chuck Finley | Randy Johnson | Mark Eichhorn | 11 | 7 | 4 |
| 1990-04-11 | vs SEA | 3 | W 1-0 | 2-1 | 4 | 25,632 | Mark Langston | Erik Hanson | Mark Langston | Gary Eave | Mike Witt | 12 | 7 | 5 |
| 1990-04-12 | vs MIN | 4 | W 3-1 | 3-1 | 2 | 24,479 | Kirk McCaskill | David West | Kirk McCaskill | David West | Mark Eichhorn | 15 | 8 | 7 |
| 1990-04-13 | vs MIN | 5 | L 4-7 | 3-2 | 3 | 33,217 | Jim Abbott | Allan Anderson | Allan Anderson | Mike Witt | Rick Aguilera | 19 | 15 | 4 |
| 1990-04-14 | vs MIN | 6 | W 7-5 | 4-2 | 3 | 34,407 | Bert Blyleven | Roy Smith | Bryan Harvey | Rick Aguilera | | 26 | 20 | 6 |
| 1990-04-15 | vs MIN | 7 | W 4-1 | 5-2 | 3 | 27,302 | Chuck Finley | Kevin Tapani | Chuck Finley | Kevin Tapani | Bryan Harvey | 30 | 21 | 9 |
| 1990-04-17 | vs OAK | 8 | L 5-7 | 5-3 | 3 | 34,370 | Mark Langston | Mike Moore | Mike Norris | Mark Eichhorn | Dennis Eckersley | 35 | 28 | 7 |
| 1990-04-18 | vs OAK | 9 | L 1-3 | 5-4 | 3 | 33,579 | Kirk McCaskill | Scott Sanderson | Scott Sanderson | Mike Witt | Gene Nelson | 36 | 31 | 5 |
| 1990-04-20 | @ MIN | 10 | L 1-13 | 5-5 | 3 | 37,975 | Jim Abbott | Kevin Tapani | Kevin Tapani | Jim Abbott | | 37 | 44 | -7 |
| 1990-04-21 | @ MIN | 11 | L 0-8 | 5-6 | 5 | 21,600 | Bert Blyleven | David West | David West | Bert Blyleven | John Candelaria | 37 | 52 | -15 |
| 1990-04-22 | @ MIN | 12 | W 5-2 | 6-6 | 4 | 20,875 | Chuck Finley | Allan Anderson | Chuck Finley | Allan Anderson | Mark Eichhorn | 42 | 54 | -12 |
| 1990-04-24 | @ BOS | 13 | L 2-4 | 6-7 | 5 | 24,362 | Mark Langston | Roger Clemens | Roger Clemens | Mark Langston | Jeff Reardon | 44 | 58 | -14 |
| 1990-04-25 | @ BOS | 14 | W 3-1 | 7-7 | 4 | 19,843 | Kirk McCaskill | Mike Boddicker | Kirk McCaskill | Mike Boddicker | Mark Eichhorn | 47 | 59 | -12 |
| 1990-04-26 | @ BOS | 15 | L 4-5 | 7-8 | 4 | 22,601 | Jim Abbott | Eric Hetzel | Lee Smith | Bryan Harvey | | 51 | 64 | -13 |
| 1990-04-27 | @ NYA | 16 | L 4-5 | 7-9 | 4 | 20,289 | Bert Blyleven | Tim Leary | Lee Guetterman | Willie Fraser | Dave Righetti | 55 | 69 | -14 |
| 1990-04-28 | @ NYA | 17 | L 2-3 | 7-10 | 5 | 25,751 | Chuck Finley | Greg Cadaret | Greg Cadaret | Chuck Finley | Dave Righetti | 57 | 72 | -15 |
| 1990-04-29 | @ NYA | 18 | W 4-3 | 8-10 | 4 | 30,098 | Mark Langston | Dave LaPoint | Mark Langston | Dave LaPoint | Bryan Harvey | 61 | 75 | -14 |
| 1990-04-30 | @ BAL | 19 | L 1-2 | 8-11 | 4 | 16,691 | Kirk McCaskill | Bob Milacki | Brian Holton | Mike Witt | | 62 | 77 | -15 |
| 1990-05-01 | @ BAL | 20 | W 7-1 | 9-11 | 4 | 21,141 | Jim Abbott | Jay Tibbs | Jim Abbott | Jay Tibbs | | 69 | 78 | -9 |
| 1990-05-02 | @ BAL | 21 | W 3-0 | 10-11 | 4 | 19,086 | Bert Blyleven | Jeff Ballard | Bert Blyleven | Jeff Ballard | Mark Eichhorn | 72 | 78 | -6 |
| 1990-05-03 | @ SEA | 22 | L 8-10 | 10-12 | 5 | 12,279 | Chuck Finley | Matt Young | Brent Knackert | Chuck Finley | Mike Schooler | 80 | 88 | -8 |
| 1990-05-04 | vs NYA | 23 | L 2-5 | 10-13 | 5 | 36,703 | Mark Langston | Dave LaPoint | Dave LaPoint | Mark Langston | | 82 | 93 | -11 |
| 1990-05-05 | vs NYA | 24 | L 3-11 | 10-14 | 6 | 47,933 | Kirk McCaskill | Clay Parker | Clay Parker | Kirk McCaskill | | 85 | 104 | -19 |
| 1990-05-06 | vs NYA | 25 | L 2-4 | 10-15 | 6 | 50,717 | Jim Abbott | Andy Hawkins | Andy Hawkins | Jim Abbott | Dave Righetti | 87 | 108 | -21 |
| 1990-05-07 | vs BAL | 26 | L 5-6 | 10-16 | 6 | 23,126 | Bert Blyleven | Jay Tibbs | Jay Tibbs | Mark Eichhorn | Gregg Olson | 92 | 114 | -22 |
| 1990-05-08 | vs BAL | 27 | W 6-0 | 11-16 | 6 | 22,803 | Chuck Finley | Jeff Ballard | Chuck Finley | Jeff Ballard | | 98 | 114 | -16 |
| 1990-05-09 | vs BAL | 28 | L 1-9 | 11-17 | 6 | 24,883 | Mark Langston | Pete Harnisch | Pete Harnisch | Mark Langston | | 99 | 123 | -24 |
| 1990-05-10 | @ SEA | 29 | L 2-5 | 11-18 | 6 | 13,958 | Kirk McCaskill | Brian Holman | Brian Holman | Kirk McCaskill | Mike Schooler | 101 | 128 | -27 |
| 1990-05-11 | vs BOS | 30 | L 2-3 | 11-19 | 6 | 33,418 | Jim Abbott | Mike Boddicker | Mike Boddicker | Mark Eichhorn | Jeff Reardon | 103 | 131 | -28 |
| 1990-05-12 | vs BOS | 31 | L 1-7 | 11-20 | 6 | 50,755 | Bert Blyleven | Greg Harris | Greg Harris | Bert Blyleven | | 104 | 138 | -34 |
| 1990-05-13 | vs BOS | 32 | W 8-4 | 12-20 | 6 | 34,399 | Chuck Finley | Eric Hetzel | Chuck Finley | Dennis Lamp | Bryan Harvey | 112 | 142 | -30 |
| 1990-05-15 | @ MIL | 33 | W 8-3 | 13-20 | 6 | 8,327 | Mark Langston | Chris Bosio | Mark Langston | Chris Bosio | | 120 | 145 | -25 |
| 1990-05-16 | @ MIL | 34 | L 5-13 | 13-21 | 6 | 12,461 | Jim Abbott | Teddy Higuera | Teddy Higuera | Jim Abbott | | 125 | 158 | -33 |
| 1990-05-17 | @ MIL | 35 | L 3-6 | 13-22 | 6 | 18,612 | Bert Blyleven | Mark Knudson | Paul Mirabella | Willie Fraser | Dan Plesac | 128 | 164 | -36 |
| 1990-05-18 | @ TOR | 36 | W 4-2 | 14-22 | 6 | 49,339 | Jim Abbott | Dave Stieb | Jim Abbott | Dave Stieb | Mark Eichhorn | 132 | 166 | -34 |
| 1990-05-19 | @ TOR | 37 | W 11-9 | 15-22 | 6 | 49,335 | Mike Fetters | John Cerutti | Willie Fraser | Duane Ward | Mark Eichhorn | 143 | 175 | -32 |
| 1990-05-20 | @ TOR | 38 | L 1-5 | 15-23 | 6 | 49,421 | Mark Langston | Willie Blair | Frank Wills | Mark Langston | Tom Henke | 144 | 180 | -36 |
| 1990-05-21 | @ CLE | 39 | W 5-3 | 16-23 | 6 | 5,637 | Bert Blyleven | Jeff Shaw | Bert Blyleven | Jeff Shaw | Mark Eichhorn | 149 | 183 | -34 |
| 1990-05-22 | @ CLE | 40 | W 8-3 | 17-23 | 6 | 7,333 | Chuck Finley | Tom Candiotti | Chuck Finley | Tom Candiotti | Bryan Harvey | 157 | 186 | -29 |
| 1990-05-23 | vs TOR | 41 | W 5-4 | 18-23 | 5 | 25,179 | Jim Abbott | Dave Stieb | Scott Bailes | Duane Ward | | 162 | 190 | -28 |
| 1990-05-24 | vs TOR | 42 | W 4-3 | 19-23 | 5 | 24,460 | Kirk McCaskill | David Wells | Bryan Harvey | Tom Henke | | 166 | 193 | -27 |
| 1990-05-25 | vs MIL | 43 | W 5-4 | 20-23 | 5 | 26,925 | Mark Langston | Chris Bosio | Willie Fraser | Tony Fossas | | 171 | 197 | -26 |
| 1990-05-26 | vs MIL | 44 | W 10-3 | 21-23 | 4 | 33,574 | Bert Blyleven | Mark Knudson | Bert Blyleven | Mark Knudson | | 181 | 200 | -19 |
| 1990-05-27 | vs MIL | 45 | W 7-3 | 22-23 | 4 | 35,466 | Chuck Finley | Bill Wegman | Chuck Finley | Bill Wegman | | 188 | 203 | -15 |
| 1990-05-28 | vs CLE | 46 | L 0-3 | 22-24 | 4 | 26,477 | Jim Abbott | Buddy Black | Cecilio Guante | Jim Abbott | Doug Jones | 188 | 206 | -18 |
| 1990-05-29 | vs CLE | 47 | W 2-1 | 23-24 | 4 | 22,429 | Kirk McCaskill | John Farrell | Kirk McCaskill | John Farrell | Mark Eichhorn | 190 | 207 | -17 |
| 1990-05-30 | vs CLE | 48 | L 2-4 | 23-25 | 4 | 25,543 | Mark Langston | Tom Candiotti | Tom Candiotti | Mark Langston | Doug Jones | 192 | 211 | -19 |
| 1990-06-01 | @ TEX | 49 | W 4-3 | 24-25 | 4 | 20,277 | Bert Blyleven | Bobby Witt | Bert Blyleven | Bobby Witt | Mark Eichhorn | 196 | 214 | -18 |
| 1990-06-02 | @ TEX | 50 | L 3-6 | 24-26 | 4 | 30,300 | Chuck Finley | Mike Jeffcoat | Mike Jeffcoat | Chuck Finley | | 199 | 220 | -21 |
| 1990-06-03 | @ TEX | 51 | W 7-4 | 25-26 | 4 | 20,173 | Jim Abbott | Charlie Hough | Jim Abbott | Charlie Hough | Bryan Harvey | 206 | 224 | -18 |
| 1990-06-04 | @ TEX | 52 | L 0-1 | 25-27 | 4 | 13,619 | Kirk McCaskill | Kevin Brown | Kevin Brown | Kirk McCaskill | Kenny Rogers | 206 | 225 | -19 |
| 1990-06-05 | @ KCA | 53 | W 6-4 | 26-27 | 4 | 23,611 | Mark Langston | Richard Dotson | Mark Langston | Richard Dotson | Bryan Harvey | 212 | 229 | -17 |
| 1990-06-06 | @ KCA | 54 | W 6-2 | 27-27 | 4 | 24,334 | Bert Blyleven | Tom Gordon | Bert Blyleven | Tom Gordon | Mark Eichhorn | 218 | 231 | -13 |
| 1990-06-07 | @ KCA | 55 | W 2-1 | 28-27 | 4 | 31,032 | Chuck Finley | Bret Saberhagen | Chuck Finley | Bret Saberhagen | Mark Eichhorn | 220 | 232 | -12 |
| 1990-06-08 | vs TEX | 56 | L 6-10 | 28-28 | 4 | 43,431 | Jim Abbott | Charlie Hough | Charlie Hough | Mike Fetters | | 226 | 242 | -16 |
| 1990-06-09 | vs TEX | 57 | W 8-3 | 29-28 | 4 | 34,226 | Kirk McCaskill | Mike Jeffcoat | Kirk McCaskill | Mike Jeffcoat | | 234 | 245 | -11 |
| 1990-06-10 | vs TEX | 58 | L 1-2 | 29-29 | 4 | 44,932 | Mark Langston | Kevin Brown | Kevin Brown | Mark Langston | | 235 | 247 | -12 |
| 1990-06-11 | vs KCA | 59 | W 3-2 | 30-29 | 4 | 26,604 | Bert Blyleven | Tom Gordon | Bert Blyleven | Mark Davis | | 238 | 249 | -11 |
| 1990-06-12 | vs KCA | 60 | W 3-0 | 31-29 | 4 | 27,250 | Chuck Finley | Bret Saberhagen | Chuck Finley | Bret Saberhagen | Bryan Harvey | 241 | 249 | -8 |
| 1990-06-13 | vs KCA | 61 | L 4-11 | 31-30 | 4 | 28,179 | Jim Abbott | Mark Gubicza | Luis Aquino | Jim Abbott | | 245 | 260 | -15 |
| 1990-06-15 | @ DET | 62 | L 1-2 | 31-31 | 4 | 21,252 | Mark Langston | Dan Petry | Jerry Gleaton | Bryan Harvey | | 246 | 262 | -16 |
| 1990-06-16 | @ DET | 63 | L 2-6 | 31-32 | 3 | 36,247 | Bert Blyleven | Jack Morris | Jack Morris | Bert Blyleven | | 248 | 268 | -20 |
| 1990-06-17 | @ DET | 64 | W 7-3 | 32-32 | 4 | 23,269 | Chuck Finley | Brian Dubois | Chuck Finley | Brian Dubois | Bryan Harvey | 255 | 271 | -16 |
| 1990-06-18 | @ CHA | 65 | W 4-1 | 33-32 | 3 | 18,868 | Jim Abbott | Jack McDowell | Jim Abbott | Jack McDowell | Bryan Harvey | 259 | 272 | -13 |
| 1990-06-19 | @ CHA | 66 | W 5-3 | 34-32 | 3 | 21,598 | Kirk McCaskill | Melido Perez | Kirk McCaskill | Melido Perez | Mark Eichhorn | 264 | 275 | -11 |
| 1990-06-20 | @ CHA | 67 | L 1-2 | 34-33 | 3 | 16,887 | Mark Langston | Greg Hibbard | Barry Jones | Mark Langston | Bobby Thigpen | 265 | 277 | -12 |
| 1990-06-21 | vs DET | 68 | W 6-4 | 35-33 | 3 | 26,462 | Bert Blyleven | Jack Morris | Bert Blyleven | Jack Morris | Bryan Harvey | 271 | 281 | -10 |
| 1990-06-22 | vs DET | 69 | W 1-0 | 36-33 | 3 | 43,253 | Chuck Finley | Brian Dubois | Scott Bailes | Paul Gibson | | 272 | 281 | -9 |
| 1990-06-23 | vs DET | 70 | L 4-9 | 36-34 | 3 | 50,527 | Jim Abbott | Jeff Robinson | Jeff Robinson | Jim Abbott | | 276 | 290 | -14 |
| 1990-06-24 | vs DET | 71 | W 10-2 | 37-34 | 3 | 35,566 | Kirk McCaskill | Frank Tanana | Kirk McCaskill | Frank Tanana | | 286 | 292 | -6 |
| 1990-06-25 | vs CHA | 72 | L 0-2 | 37-35 | 3 | 27,357 | Mark Langston | Greg Hibbard | Greg Hibbard | Mark Langston | Bobby Thigpen | 286 | 294 | -8 |
| 1990-06-26 | vs CHA | 73 | L 9-11 | 37-36 | 3 | 28,401 | Bert Blyleven | Adam Peterson | Barry Jones | Mark Eichhorn | Bobby Thigpen | 295 | 305 | -10 |
| 1990-06-27 | vs CHA | 74 | L 2-5 | 37-37 | 3 | 34,020 | Chuck Finley | Eric King | Eric King | Chuck Finley | Scott Radinsky | 297 | 310 | -13 |
| 1990-06-29 | @ CLE | 75 | W 7-2 | 38-37 | 3 | 20,736 | Jim Abbott | Charles Nagy | Jim Abbott | Charles Nagy | | 304 | 312 | -8 |
| 1990-06-30 | @ CLE | 76 | L 1-4 | 38-38 | 4 | 18,930 | Kirk McCaskill | Tom Candiotti | Tom Candiotti | Kirk McCaskill | Doug Jones | 305 | 316 | -11 |
| 1990-07-01 | @ CLE | 77 | L 3-5 | 38-39 | 4 | 27,001 | Mark Langston | Greg Swindell | Greg Swindell | Mark Langston | Doug Jones | 308 | 321 | -13 |
| 1990-07-02 | @ CLE | 78 | W 2-1 | 39-39 | 4 | 12,309 | Chuck Finley | Buddy Black | Chuck Finley | Jesse Orosco | Bryan Harvey | 310 | 322 | -12 |
| 1990-07-03 | @ TOR | 79 | L 2-5 | 39-40 | 4 | 49,836 | Bert Blyleven | Todd Stottlemyre | Todd Stottlemyre | Bert Blyleven | Tom Henke | 312 | 327 | -15 |
| 1990-07-04 | @ TOR | 80 | L 2-4 | 39-41 | 4 | 49,831 | Jim Abbott | John Cerutti | John Cerutti | Jim Abbott | Tom Henke | 314 | 331 | -17 |
| 1990-07-05 | @ TOR | 81 | L 2-9 | 39-42 | 4 | 49,838 | Kirk McCaskill | Dave Stieb | Dave Stieb | Kirk McCaskill | | 316 | 340 | -24 |
| 1990-07-06 | @ MIL | 82 | W 9-8 | 40-42 | 4 | 25,244 | Mark Langston | Dennis Powell | Greg Minton | Tom Edens | | 325 | 348 | -23 |
| 1990-07-07 | @ MIL | 83 | W 4-3 | 41-42 | 4 | 27,717 | Chuck Finley | Mark Knudson | Mike Fetters | Randy Veres | | 329 | 351 | -22 |
| 1990-07-08 | @ MIL | 84 | L 7-20 | 41-43 | 4 | 29,476 | Bert Blyleven | Bill Krueger | Tom Edens | Greg Minton | | 336 | 371 | -35 |
| 1990-07-11 | @ SEA | 85 | L 1-2 | 41-44 | 4 | 18,357 | Mark Langston | Erik Hanson | Erik Hanson | Mark Langston | Mike Schooler | 337 | 373 | -36 |
| 1990-07-12 | vs TOR | 86 | L 0-5 | 41-45 | 5 | 27,365 | Kirk McCaskill | David Wells | David Wells | Kirk McCaskill | | 337 | 378 | -41 |
| 1990-07-13 | vs TOR | 87 | W 2-0 | 42-45 | 5 | 35,001 | Jim Abbott | Todd Stottlemyre | Jim Abbott | Todd Stottlemyre | | 339 | 378 | -39 |
| 1990-07-14 | vs TOR | 88 | W 8-7 | 43-45 | 5 | 34,466 | Bert Blyleven | John Cerutti | Mark Eichhorn | Duane Ward | | 347 | 385 | -38 |
| 1990-07-15 | vs TOR | 89 | W 3-2 | 44-45 | 4 | 31,609 | Chuck Finley | Dave Stieb | Chuck Finley | Tom Henke | | 350 | 387 | -37 |
| 1990-07-16 | vs MIL | 90 | L 1-3 | 44-46 | 4 | 24,643 | Mark Langston | Ron Robinson | Ron Robinson | Mark Langston | Dan Plesac | 351 | 390 | -39 |
| 1990-07-17 | vs MIL | 91 | W 8-1 | 45-46 | 4 | 27,363 | Kirk McCaskill | Teddy Higuera | Kirk McCaskill | Teddy Higuera | | 359 | 391 | -32 |
| 1990-07-18 | vs MIL | 92 | L 2-3 | 45-47 | 4 | 36,000 | Jim Abbott | Mark Knudson | Mark Knudson | Jim Abbott | Dan Plesac | 361 | 394 | -33 |
| 1990-07-20 | vs CLE | 93 | W 9-4 | 46-47 | 4 | 32,254 | Bert Blyleven | Buddy Black | Bert Blyleven | Buddy Black | Mike Fetters | 370 | 398 | -28 |
| 1990-07-21 | vs CLE | 94 | W 5-2 | 47-47 | 4 | 32,761 | Chuck Finley | Mike Walker | Chuck Finley | Mike Walker | | 375 | 400 | -25 |
| 1990-07-22 | vs CLE | 95 | L 1-8 | 47-48 | 4 | 32,126 | Mark Langston | Greg Swindell | Greg Swindell | Mark Langston | | 376 | 408 | -32 |
| 1990-07-23 | @ OAK | 96 | L 6-7 | 47-49 | 5 | 31,252 | Kirk McCaskill | Dave Stewart | Gene Nelson | Cliff Young | | 382 | 415 | -33 |
| 1990-07-24 | @ OAK | 97 | L 3-5 | 47-50 | 5 | 37,906 | Jim Abbott | Bob Welch | Bob Welch | Jim Abbott | Dennis Eckersley | 385 | 420 | -35 |
| 1990-07-25 | @ OAK | 98 | L 3-13 | 47-51 | 5 | 35,587 | Bert Blyleven | Curt Young | Curt Young | Bert Blyleven | Todd Burns | 388 | 433 | -45 |
| 1990-07-26 | @ OAK | 99 | W 4-2 | 48-51 | 5 | 35,188 | Chuck Finley | Scott Sanderson | Bryan Harvey | Dennis Eckersley | | 392 | 435 | -43 |
| 1990-07-27 | @ SEA | 100 | L 1-8 | 48-52 | 5 | 19,260 | Mark Langston | Erik Hanson | Erik Hanson | Mark Langston | | 393 | 443 | -50 |
| 1990-07-28 | @ SEA | 101 | L 1-2 | 48-53 | 6 | 28,039 | Kirk McCaskill | Brian Holman | Brian Holman | Kirk McCaskill | Mike Schooler | 394 | 445 | -51 |
| 1990-07-29 | @ SEA | 102 | W 6-2 | 49-53 | 6 | 18,388 | Jim Abbott | Matt Young | Jim Abbott | Matt Young | Bryan Harvey | 400 | 447 | -47 |
| 1990-07-30 | @ MIN | 103 | L 3-7 | 49-54 | 6 | 19,608 | Bert Blyleven | Kevin Tapani | Kevin Tapani | Bert Blyleven | Terry Leach | 403 | 454 | -51 |
| 1990-07-31 | @ MIN | 104 | W 13-2 | 50-54 | 6 | 20,607 | Chuck Finley | Allan Anderson | Chuck Finley | Allan Anderson | | 416 | 456 | -40 |
| 1990-08-01 | @ MIN | 105 | W 11-5 | 51-54 | 5 | 21,260 | Mark Langston | Roy Smith | Mark Langston | Roy Smith | Bryan Harvey | 427 | 461 | -34 |
| 1990-08-02 | vs OAK | 106 | L 5-7 | 51-55 | 5 | 38,698 | Kirk McCaskill | Bob Welch | Bob Welch | Kirk McCaskill | Dennis Eckersley | 432 | 468 | -36 |
| 1990-08-03 | vs OAK | 107 | L 6-8 | 51-56 | 6 | 45,457 | Jim Abbott | Scott Sanderson | Reggie Harris | Willie Fraser | Dennis Eckersley | 438 | 476 | -38 |
| 1990-08-04 | vs OAK | 108 | W 6-5 | 52-56 | 5 | 52,774 | Joe Grahe | Mike Moore | Mark Eichhorn | Todd Burns | | 444 | 481 | -37 |
| 1990-08-05 | vs OAK | 109 | L 1-4 | 52-57 | 5 | 51,597 | Chuck Finley | Dave Stewart | Dave Stewart | Chuck Finley | Dennis Eckersley | 445 | 485 | -40 |
| 1990-08-07 | vs BOS | 110 | L 3-6 | 52-58 | 5 | 29,262 | Mark Langston | Tom Bolton | Tom Bolton | Mark Langston | Rob Murphy | 448 | 491 | -43 |
| 1990-08-08 | vs BOS | 111 | W 8-6 | 53-58 | 5 | 29,362 | Kirk McCaskill | Greg Harris | Willie Fraser | Dennis Lamp | | 456 | 497 | -41 |
| 1990-08-09 | vs BOS | 112 | L 3-14 | 53-59 | 5 | 32,802 | Jim Abbott | Roger Clemens | Roger Clemens | Jim Abbott | | 459 | 511 | -52 |
| 1990-08-10 | vs BAL | 113 | W 2-1 | 54-59 | 6 | 42,195 | Bert Blyleven | Pete Harnisch | Willie Fraser | Gregg Olson | | 461 | 512 | -51 |
| 1990-08-11 | vs BAL | 114 | W 12-4 | 55-59 | 5 | 30,040 | Chuck Finley | Mickey Weston | Chuck Finley | Mickey Weston | | 473 | 516 | -43 |
| 1990-08-12 | vs BAL | 115 | L 6-11 | 55-60 | 6 | 33,657 | Mark Langston | John Mitchell | John Mitchell | Mark Langston | Mark Williamson | 479 | 527 | -48 |
| 1990-08-13 | vs NYA | 116 | W 4-2 | 56-60 | 6 | 28,387 | Kirk McCaskill | Chuck Cary | Kirk McCaskill | Chuck Cary | Bryan Harvey | 483 | 529 | -46 |
| 1990-08-14 | vs NYA | 117 | W 9-5 | 57-60 | 6 | 27,937 | Jim Abbott | Tim Leary | Jim Abbott | Tim Leary | Willie Fraser | 492 | 534 | -42 |
| 1990-08-15 | vs NYA | 118 | W 8-1 | 58-60 | 5 | 29,845 | Mark Langston | Dave LaPoint | Mark Langston | Dave LaPoint | | 500 | 535 | -35 |
| 1990-08-17 | @ BOS | 119 | W 1-0 | 59-60 | 5 | 35,107 | Chuck Finley | Mike Boddicker | Chuck Finley | Mike Boddicker | | 501 | 535 | -34 |
| 1990-08-18 | @ BOS | 120 | W 4-3 | 60-60 | 5 | 34,131 | Kirk McCaskill | Tom Bolton | Kirk McCaskill | Tom Bolton | Bryan Harvey | 505 | 538 | -33 |
| 1990-08-19 | @ BOS | 121 | L 1-4 | 60-61 | 5 | 33,365 | Jim Abbott | Roger Clemens | Roger Clemens | Jim Abbott | Jeff Gray | 506 | 542 | -36 |
| 1990-08-20 | @ DET | 122 | W 5-3 | 61-61 | 4 | 13,349 | Mark Langston | Jeff Robinson | Mark Langston | Paul Gibson | Bryan Harvey | 511 | 545 | -34 |
| 1990-08-21 | @ DET | 123 | L 2-6 | 61-62 | 5 | 14,916 | Joe Grahe | Dan Petry | Dan Petry | Joe Grahe | Ed Nunez | 513 | 551 | -38 |
| 1990-08-22 | @ DET | 124 | L 4-7 | 61-63 | 6 | 21,375 | Chuck Finley | Jack Morris | Jack Morris | Chuck Finley | Jerry Gleaton | 517 | 558 | -41 |
| 1990-08-23 | @ CHA | 125 | L 2-4 | 61-64 | 6 | 32,393 | Kirk McCaskill | Alex Fernandez | Alex Fernandez | Kirk McCaskill | Bobby Thigpen | 519 | 562 | -43 |
| 1990-08-24 | @ CHA | 126 | L 2-5 | 61-65 | 6 | 29,024 | Jim Abbott | Wayne Edwards | Wayne Edwards | Jim Abbott | Bobby Thigpen | 521 | 567 | -46 |
| 1990-08-25 | @ CHA | 127 | W 3-2 | 62-65 | 6 | 37,079 | Mark Langston | Jack McDowell | Mark Langston | Bobby Thigpen | Bryan Harvey | 524 | 569 | -45 |
| 1990-08-26 | @ CHA | 128 | W 4-1 | 63-65 | 5 | 34,249 | Joe Grahe | Greg Hibbard | Joe Grahe | Greg Hibbard | Bryan Harvey | 528 | 570 | -42 |
| 1990-08-27 | vs TEX | 129 | W 7-3 | 64-65 | 5 | 23,915 | Chuck Finley | Charlie Hough | Willie Fraser | John Barfield | Bryan Harvey | 535 | 573 | -38 |
| 1990-08-28 | vs TEX | 130 | W 2-0 | 65-65 | 5 | 37,692 | Kirk McCaskill | Nolan Ryan | Kirk McCaskill | Nolan Ryan | | 537 | 573 | -36 |
| 1990-08-29 | vs TEX | 131 | W 9-2 | 66-65 | 5 | 25,575 | Jim Abbott | Kevin Brown | Jim Abbott | John Barfield | | 546 | 575 | -29 |
| 1990-08-31 | vs CHA | 132 | L 5-6 | 66-66 | 4 | 26,657 | Mark Langston | Greg Hibbard | Greg Hibbard | Mark Langston | Bobby Thigpen | 551 | 581 | -30 |
| 1990-09-01 | vs CHA | 133 | L 5-9 | 66-67 | 4 | 29,491 | Joe Grahe | Melido Perez | Melido Perez | Joe Grahe | Bobby Thigpen | 556 | 590 | -34 |
| 1990-09-02 | vs CHA | 134 | W 1-0 | 67-67 | 4 | 25,167 | Chuck Finley | Alex Fernandez | Chuck Finley | Alex Fernandez | Bryan Harvey | 557 | 590 | -33 |
| 1990-09-03 | @ NYA | 135 | W 7-0 | 68-67 | 4 | 27,013 | Kirk McCaskill | Tim Leary | Kirk McCaskill | Tim Leary | Willie Fraser | 564 | 590 | -26 |
| 1990-09-05 | @ NYA | 136 | L 1-2 | 68-68 | 4 | 23,010 | Jim Abbott | Dave LaPoint | Dave LaPoint | Bryan Harvey | Dave Righetti | 565 | 592 | -27 |
| 1990-09-06 | @ NYA | 137 | W 12-6 | 69-68 | 4 | 18,707 | Mark Langston | Chuck Cary | Bob McClure | Lee Guetterman | | 577 | 598 | -21 |
| 1990-09-07 | @ BAL | 138 | L 2-6 | 69-69 | 4 | 22,499 | Joe Grahe | Ben McDonald | Ben McDonald | Joe Grahe | | 579 | 604 | -25 |
| 1990-09-08 | @ BAL | 139 | L 4-5 | 69-70 | 4 | 30,738 | Chuck Finley | Jose Mesa | Joe Price | Mark Eichhorn | | 583 | 609 | -26 |
| 1990-09-09 | @ BAL | 140 | L 1-3 | 69-71 | 5 | 30,066 | Kirk McCaskill | Anthony Telford | Anthony Telford | Kirk McCaskill | Gregg Olson | 584 | 612 | -28 |
| 1990-09-10 | vs MIN | 141 | W 3-1 | 70-71 | 5 | 21,379 | Jim Abbott | Paul Abbott | Jim Abbott | Paul Abbott | Bryan Harvey | 587 | 613 | -26 |
| 1990-09-11 | vs MIN | 142 | W 9-0 | 71-71 | 4 | 21,908 | Mark Langston | Kevin Tapani | Mark Langston | Kevin Tapani | | 596 | 613 | -17 |
| 1990-09-12 | vs MIN | 143 | W 8-6 | 72-71 | 4 | 21,480 | Joe Grahe | Larry Casian | Joe Grahe | Tim Drummond | Bryan Harvey | 604 | 619 | -15 |
| 1990-09-13 | vs SEA | 144 | W 7-1 | 73-71 | 4 | 21,683 | Chuck Finley | Rich DeLucia | Chuck Finley | Keith Comstock | | 611 | 620 | -9 |
| 1990-09-14 | vs SEA | 145 | W 7-5 | 74-71 | 4 | 34,180 | Kirk McCaskill | Matt Young | Bob McClure | Matt Young | Bryan Harvey | 618 | 625 | -7 |
| 1990-09-15 | vs SEA | 146 | L 2-7 | 74-72 | 4 | 27,948 | Jim Abbott | Erik Hanson | Erik Hanson | Jim Abbott | | 620 | 632 | -12 |
| 1990-09-16 | vs SEA | 147 | L 3-5 | 74-73 | 4 | 30,000 | Mark Langston | Randy Johnson | Bill Swift | Bryan Harvey | Michael Jackson | 623 | 637 | -14 |
| 1990-09-18 | vs DET | 148 | L 2-3 | 74-74 | 4 | 22,397 | Chuck Finley | Jack Morris | Jack Morris | Chuck Finley | Mike Henneman | 625 | 640 | -15 |
| 1990-09-19 | vs DET | 149 | L 5-12 | 74-75 | 4 | 21,770 | Joe Grahe | Walt Terrell | Walt Terrell | Joe Grahe | Jerry Gleaton | 630 | 652 | -22 |
| 1990-09-21 | @ KCA | 150 | W 12-5 | 75-75 | 4 | 22,210 | Kirk McCaskill | Bret Saberhagen | Kirk McCaskill | Bret Saberhagen | | 642 | 657 | -15 |
| 1990-09-22 | @ KCA | 151 | L 3-4 | 75-76 | 4 | 27,379 | Jim Abbott | Hector Wagner | Mark Davis | Jim Abbott | Jeff Montgomery | 645 | 661 | -16 |
| 1990-09-23 | @ KCA | 152 | L 0-4 | 75-77 | 4 | 23,045 | Chuck Finley | Steve Farr | Steve Farr | Chuck Finley | | 645 | 665 | -20 |
| 1990-09-24 | @ TEX | 153 | W 3-2 | 76-77 | 4 | 12,504 | Mark Langston | Nolan Ryan | Mark Langston | Nolan Ryan | Bryan Harvey | 648 | 667 | -19 |
| 1990-09-25 | @ TEX | 154 | W 8-2 | 77-77 | 4 | 12,000 | Scott Lewis | Bobby Witt | Scott Lewis | Bobby Witt | | 656 | 669 | -13 |
| 1990-09-26 | @ TEX | 155 | L 2-6 | 77-78 | 4 | 18,761 | Kirk McCaskill | Kenny Rogers | Kenny Rogers | Kirk McCaskill | | 658 | 675 | -17 |
| 1990-09-27 | vs KCA | 156 | W 7-6 | 78-78 | 4 | 22,281 | Jim Abbott | Hector Wagner | Bryan Harvey | Jeff Montgomery | | 665 | 681 | -16 |
| 1990-09-28 | vs KCA | 157 | L 1-2 | 78-79 | 4 | 25,860 | Chuck Finley | Steve Farr | Steve Farr | Chuck Finley | Jeff Montgomery | 666 | 683 | -17 |
| 1990-09-29 | vs KCA | 158 | L 6-9 | 78-80 | 4 | 29,114 | Mark Langston | Tom Gordon | Andy McGaffigan | Mark Langston | Jeff Montgomery | 672 | 692 | -20 |
| 1990-09-30 | vs KCA | 159 | L 1-2 | 78-81 | 4 | 34,644 | Scott Lewis | Kevin Appier | Kevin Appier | Scott Lewis | Jeff Montgomery | 673 | 694 | -21 |
| 1990-10-01 | @ OAK | 160 | W 2-0 | 79-81 | 4 | 31,378 | Joe Grahe | Dave Stewart | Joe Grahe | Dave Stewart | Bryan Harvey | 675 | 694 | -19 |
| 1990-10-02 | @ OAK | 161 | L 4-6 | 79-82 | 4 | 29,042 | Jim Abbott | Bob Welch | Bob Welch | Willie Fraser | Dennis Eckersley | 679 | 700 | -21 |
| 1990-10-03 | @ OAK | 162 | W 11-6 | 80-82 | 4 | 24,225 | Mike Fetters | Mike Moore | Cliff Young | Mike Moore | | 690 | 706 | -16 |