| 1988-04-04 | vs TOR | 1 | L 3-5 | 0-1 | 4 | 40,648 | Bret Saberhagen | Jimmy Key | Jimmy Key | Bret Saberhagen | Tom Henke | 3 | 5 | -2 |
| 1988-04-06 | vs TOR | 2 | L 4-11 | 0-2 | 6 | 18,938 | Charlie Leibrandt | Mike Flanagan | Mike Flanagan | Charlie Leibrandt | | 7 | 16 | -9 |
| 1988-04-07 | vs TOR | 3 | W 7-4 | 1-2 | 3 | 29,070 | Mark Gubicza | Jim Clancy | Mark Gubicza | Jim Clancy | | 14 | 20 | -6 |
| 1988-04-08 | vs DET | 4 | W 3-2 | 2-2 | 3 | 26,159 | Floyd Bannister | Jeff Robinson | Floyd Bannister | Jeff Robinson | Gene Garber | 17 | 22 | -5 |
| 1988-04-09 | vs DET | 5 | L 4-11 | 2-3 | 3 | 23,418 | Bret Saberhagen | Jack Morris | Jack Morris | Buddy Black | | 21 | 33 | -12 |
| 1988-04-10 | vs DET | 6 | W 8-1 | 3-3 | 3 | 26,305 | Charlie Leibrandt | Doyle Alexander | Charlie Leibrandt | Doyle Alexander | | 29 | 34 | -5 |
| 1988-04-12 | @ BAL | 7 | W 6-1 | 4-3 | 1 | 11,180 | Mark Gubicza | Oswaldo Peraza | Mark Gubicza | Oswaldo Peraza | | 35 | 35 | 0 |
| 1988-04-13 | @ BAL | 8 | W 9-3 | 5-3 | 1 | 12,027 | Floyd Bannister | Mark Thurmond | Floyd Bannister | Mark Thurmond | | 44 | 38 | 6 |
| 1988-04-14 | @ BAL | 9 | W 4-3 | 6-3 | 1 | 13,005 | Bret Saberhagen | Mike Boddicker | Bret Saberhagen | Mike Boddicker | Gene Garber | 48 | 41 | 7 |
| 1988-04-16 | @ DET | 10 | L 2-4 | 6-4 | 1 | 18,480 | Charlie Leibrandt | Doyle Alexander | Doyle Alexander | Charlie Leibrandt | Mike Henneman | 50 | 45 | 5 |
| 1988-04-17 | @ DET | 11 | L 6-8 | 6-5 | 2 | 18,292 | Mark Gubicza | Jeff Robinson | Jeff Robinson | Mark Gubicza | Mike Henneman | 56 | 53 | 3 |
| 1988-04-18 | @ DET | 12 | L 2-4 | 6-6 | 3 | 11,001 | Floyd Bannister | Frank Tanana | Frank Tanana | Floyd Bannister | Mike Henneman | 58 | 57 | 1 |
| 1988-04-19 | @ TOR | 13 | L 3-12 | 6-7 | 3 | 21,231 | Bret Saberhagen | Jim Clancy | Jim Clancy | Bret Saberhagen | | 61 | 69 | -8 |
| 1988-04-20 | @ TOR | 14 | L 0-3 | 6-8 | 3 | 20,202 | Charlie Leibrandt | Dave Stieb | Dave Stieb | Charlie Leibrandt | Tom Henke | 61 | 72 | -11 |
| 1988-04-22 | vs BAL | 15 | W 13-1 | 7-8 | 3 | 34,482 | Mark Gubicza | Mike Morgan | Mark Gubicza | Mike Morgan | | 74 | 73 | 1 |
| 1988-04-23 | vs BAL | 16 | W 4-3 | 8-8 | 3 | 23,564 | Floyd Bannister | Mark Williamson | Ted Power | Doug Sisk | | 78 | 76 | 2 |
| 1988-04-24 | vs BAL | 17 | W 3-1 | 9-8 | 2 | 25,526 | Bret Saberhagen | Mark Thurmond | Bret Saberhagen | Mark Thurmond | | 81 | 77 | 4 |
| 1988-04-26 | @ NYA | 18 | L 4-5 | 9-9 | 3 | 20,364 | Charlie Leibrandt | Al Leiter | Cecilio Guante | Charlie Leibrandt | Charles Hudson | 85 | 82 | 3 |
| 1988-04-27 | @ NYA | 19 | W 3-1 | 10-9 | 2 | 20,484 | Mark Gubicza | Tommy John | Buddy Black | Charles Hudson | Gene Garber | 88 | 83 | 5 |
| 1988-04-28 | @ NYA | 20 | W 6-3 | 11-9 | 2 | 17,102 | Floyd Bannister | Rick Rhoden | Floyd Bannister | Rick Rhoden | Dan Quisenberry | 94 | 86 | 8 |
| 1988-04-29 | @ MIL | 21 | W 7-2 | 12-9 | 2 | 12,350 | Bret Saberhagen | Mike Birkbeck | Bret Saberhagen | Mike Birkbeck | | 101 | 88 | 13 |
| 1988-04-30 | @ MIL | 22 | L 1-4 | 12-10 | 2 | 26,288 | Charlie Leibrandt | Bill Wegman | Bill Wegman | Charlie Leibrandt | Dan Plesac | 102 | 92 | 10 |
| 1988-05-01 | @ MIL | 23 | L 6-10 | 12-11 | 3 | 17,562 | Mark Gubicza | Chris Bosio | Chris Bosio | Mark Gubicza | Dan Plesac | 108 | 102 | 6 |
| 1988-05-02 | @ BOS | 24 | W 2-0 | 13-11 | 2 | 20,400 | Floyd Bannister | Steve Ellsworth | Floyd Bannister | Steve Ellsworth | Gene Garber | 110 | 102 | 8 |
| 1988-05-03 | @ BOS | 25 | W 9-3 | 14-11 | 2 | 21,602 | Bret Saberhagen | Oil Can Boyd | Bret Saberhagen | Oil Can Boyd | | 119 | 105 | 14 |
| 1988-05-04 | vs NYA | 26 | L 3-4 | 14-12 | 2 | 27,422 | Charlie Leibrandt | John Candelaria | John Candelaria | Ted Power | Tim Stoddard | 122 | 109 | 13 |
| 1988-05-05 | vs NYA | 27 | L 3-5 | 14-13 | 2 | 36,255 | Mark Gubicza | Richard Dotson | Richard Dotson | Mark Gubicza | Cecilio Guante | 125 | 114 | 11 |
| 1988-05-06 | vs MIL | 28 | L 0-4 | 14-14 | 3 | 25,460 | Floyd Bannister | Chris Bosio | Chris Bosio | Floyd Bannister | | 125 | 118 | 7 |
| 1988-05-07 | vs MIL | 29 | L 2-4 | 14-15 | 3 | 28,002 | Bret Saberhagen | Juan Nieves | Juan Nieves | Bret Saberhagen | Dan Plesac | 127 | 122 | 5 |
| 1988-05-08 | vs MIL | 30 | L 2-6 | 14-16 | 3 | 22,603 | Charlie Leibrandt | Teddy Higuera | Dan Plesac | Dan Quisenberry | | 129 | 128 | 1 |
| 1988-05-09 | vs BOS | 31 | L 0-2 | 14-17 | 3 | 24,806 | Mark Gubicza | Roger Clemens | Roger Clemens | Mark Gubicza | | 129 | 130 | -1 |
| 1988-05-10 | vs BOS | 32 | W 7-2 | 15-17 | 3 | 21,645 | Floyd Bannister | Bruce Hurst | Floyd Bannister | Bruce Hurst | | 136 | 132 | 4 |
| 1988-05-13 | @ TEX | 33 | L 1-2 | 15-18 | 4 | 21,898 | Bret Saberhagen | Ray Hayward | Ray Hayward | Bret Saberhagen | Mitch Williams | 137 | 134 | 3 |
| 1988-05-14 | @ TEX | 34 | L 3-6 | 15-19 | 4 | 31,251 | Charlie Leibrandt | Jeff Russell | Jeff Russell | Charlie Leibrandt | Mitch Williams | 140 | 140 | 0 |
| 1988-05-15 | @ TEX | 35 | W 5-4 | 16-19 | 4 | 30,438 | Mark Gubicza | Charlie Hough | Mark Gubicza | Charlie Hough | Gene Garber | 145 | 144 | 1 |
| 1988-05-16 | @ TEX | 36 | W 7-6 | 17-19 | 4 | 15,532 | Floyd Bannister | Paul Kilgus | Floyd Bannister | Paul Kilgus | Steve Farr | 152 | 150 | 2 |
| 1988-05-17 | @ MIN | 37 | L 5-6 | 17-20 | 4 | 24,808 | Ted Power | Bert Blyleven | Juan Berenguer | Gene Garber | | 157 | 156 | 1 |
| 1988-05-18 | @ MIN | 38 | W 8-2 | 18-20 | 4 | 23,518 | Bret Saberhagen | Allan Anderson | Bret Saberhagen | Allan Anderson | | 165 | 158 | 7 |
| 1988-05-19 | @ MIN | 39 | W 14-1 | 19-20 | 3 | 26,860 | Charlie Leibrandt | Les Straker | Charlie Leibrandt | Les Straker | | 179 | 159 | 20 |
| 1988-05-20 | vs CLE | 40 | W 4-3 | 20-20 | 3 | 25,528 | Mark Gubicza | John Farrell | Mark Gubicza | John Farrell | Steve Farr | 183 | 162 | 21 |
| 1988-05-21 | vs CLE | 41 | L 5-9 | 20-21 | 3 | 35,941 | Floyd Bannister | Scott Bailes | Scott Bailes | Floyd Bannister | Doug Jones | 188 | 171 | 17 |
| 1988-05-22 | vs CLE | 42 | L 7-8 | 20-22 | 3 | 33,936 | Ted Power | Rich Yett | Bill Laskey | Gene Garber | Doug Jones | 195 | 179 | 16 |
| 1988-05-23 | vs MIN | 43 | L 5-7 | 20-23 | 3 | 27,231 | Bret Saberhagen | Allan Anderson | Keith Atherton | Bret Saberhagen | Jeff Reardon | 200 | 186 | 14 |
| 1988-05-24 | vs MIN | 44 | L 5-6 | 20-24 | 4 | 24,863 | Charlie Leibrandt | Charlie Lea | Charlie Lea | Charlie Leibrandt | Jeff Reardon | 205 | 192 | 13 |
| 1988-05-25 | vs MIN | 45 | L 2-4 | 20-25 | 4 | 22,022 | Mark Gubicza | Bert Blyleven | Bert Blyleven | Mark Gubicza | Jeff Reardon | 207 | 196 | 11 |
| 1988-05-27 | vs TEX | 46 | L 2-3 | 20-26 | 4 | 24,045 | Floyd Bannister | Jose Guzman | Jose Guzman | Floyd Bannister | | 209 | 199 | 10 |
| 1988-05-28 | vs TEX | 47 | W 8-6 | 21-26 | 4 | 37,802 | Ted Power | Charlie Hough | Buddy Black | Dale Mohorcic | Jerry Gleaton | 217 | 205 | 12 |
| 1988-05-29 | vs TEX | 48 | W 12-1 | 22-26 | 4 | 31,118 | Bret Saberhagen | Ray Hayward | Bret Saberhagen | Ray Hayward | | 229 | 206 | 23 |
| 1988-05-30 | @ CLE | 49 | L 1-4 | 22-27 | 4 | 33,533 | Charlie Leibrandt | Greg Swindell | Greg Swindell | Charlie Leibrandt | Doug Jones | 230 | 210 | 20 |
| 1988-05-31 | @ CLE | 50 | W 6-3 | 23-27 | 4 | 8,978 | Mark Gubicza | John Farrell | Mark Gubicza | Dan Schatzeder | Steve Farr | 236 | 213 | 23 |
| 1988-06-01 | @ CLE | 51 | L 4-5 | 23-28 | 4 | 8,732 | Floyd Bannister | Scott Bailes | Scott Bailes | Floyd Bannister | Doug Jones | 240 | 218 | 22 |
| 1988-06-02 | vs SEA | 52 | W 3-0 | 24-28 | 4 | 24,546 | Ted Power | Bill Swift | Ted Power | Bill Swift | | 243 | 218 | 25 |
| 1988-06-03 | vs SEA | 53 | W 3-1 | 25-28 | 4 | 34,163 | Bret Saberhagen | Mike Campbell | Bret Saberhagen | Mike Campbell | | 246 | 219 | 27 |
| 1988-06-04 | vs SEA | 54 | W 4-3 | 26-28 | 4 | 33,394 | Charlie Leibrandt | Mark Langston | Steve Farr | Mark Langston | | 250 | 222 | 28 |
| 1988-06-05 | vs SEA | 55 | W 7-3 | 27-28 | 4 | 27,601 | Mark Gubicza | Ed Nunez | Mark Gubicza | Ed Nunez | | 257 | 225 | 32 |
| 1988-06-06 | vs OAK | 56 | W 2-0 | 28-28 | 4 | 36,724 | Steve Farr | Steve Ontiveros | Steve Farr | Steve Ontiveros | Jerry Gleaton | 259 | 225 | 34 |
| 1988-06-07 | vs OAK | 57 | W 6-0 | 29-28 | 3 | 34,083 | Ted Power | Curt Young | Ted Power | Curt Young | | 265 | 225 | 40 |
| 1988-06-08 | vs OAK | 58 | W 5-4 | 30-28 | 3 | 32,002 | Bret Saberhagen | Dave Stewart | Bret Saberhagen | Dave Stewart | Jeff Montgomery | 270 | 229 | 41 |
| 1988-06-10 | @ CAL | 59 | L 0-1 | 30-29 | 3 | 38,642 | Charlie Leibrandt | Dan Petry | Dan Petry | Charlie Leibrandt | | 270 | 230 | 40 |
| 1988-06-11 | @ CAL | 60 | W 7-0 | 31-29 | 3 | 30,355 | Mark Gubicza | Kirk McCaskill | Mark Gubicza | Kirk McCaskill | | 277 | 230 | 47 |
| 1988-06-12 | @ CAL | 61 | W 6-4 | 32-29 | 3 | 36,931 | Ted Power | Willie Fraser | Ted Power | Willie Fraser | | 283 | 234 | 49 |
| 1988-06-13 | @ CAL | 62 | W 5-3 | 33-29 | 3 | 23,111 | Floyd Bannister | Chuck Finley | Floyd Bannister | Chuck Finley | Steve Farr | 288 | 237 | 51 |
| 1988-06-14 | @ OAK | 63 | W 2-1 | 34-29 | 3 | 21,380 | Bret Saberhagen | Storm Davis | Bret Saberhagen | Greg Cadaret | Gene Garber | 290 | 238 | 52 |
| 1988-06-15 | @ OAK | 64 | W 2-0 | 35-29 | 3 | 17,174 | Charlie Leibrandt | Bob Welch | Charlie Leibrandt | Bob Welch | | 292 | 238 | 54 |
| 1988-06-16 | @ OAK | 65 | W 9-5 | 36-29 | 2 | 23,579 | Mark Gubicza | Curt Young | Mark Gubicza | Curt Young | | 301 | 243 | 58 |
| 1988-06-17 | vs CAL | 66 | L 7-9 | 36-30 | 3 | 33,236 | Ted Power | Willie Fraser | Stew Cliburn | Gene Garber | | 308 | 252 | 56 |
| 1988-06-18 | vs CAL | 67 | L 3-6 | 36-31 | 3 | 40,642 | Floyd Bannister | Chuck Finley | Greg Minton | Jerry Gleaton | | 311 | 258 | 53 |
| 1988-06-19 | vs CAL | 68 | L 0-5 | 36-32 | 3 | 36,674 | Bret Saberhagen | Mike Witt | Mike Witt | Bret Saberhagen | | 311 | 263 | 48 |
| 1988-06-20 | @ CHA | 69 | L 3-5 | 36-33 | 3 | 13,973 | Charlie Leibrandt | Jack McDowell | Bobby Thigpen | Jeff Montgomery | | 314 | 268 | 46 |
| 1988-06-21 | @ CHA | 70 | W 6-2 | 37-33 | 3 | 9,769 | Mark Gubicza | Jerry Reuss | Mark Gubicza | Jerry Reuss | | 320 | 270 | 50 |
| 1988-06-22 | @ CHA | 71 | L 4-5 | 37-34 | 3 | 9,668 | Rick Anderson | Bill Long | Bobby Thigpen | Steve Farr | | 324 | 275 | 49 |
| 1988-06-24 | @ SEA | 72 | L 0-7 | 37-35 | 3 | 11,167 | Floyd Bannister | Mike Moore | Mike Moore | Floyd Bannister | | 324 | 282 | 42 |
| 1988-06-25 | @ SEA | 73 | W 7-3 | 38-35 | 3 | 13,289 | Bret Saberhagen | Mark Langston | Bret Saberhagen | Mark Langston | | 331 | 285 | 46 |
| 1988-06-26 | @ SEA | 74 | L 0-8 | 38-36 | 3 | 11,668 | Charlie Leibrandt | Bill Swift | Bill Swift | Charlie Leibrandt | | 331 | 293 | 38 |
| 1988-06-27 | vs CHA | 75 | W 2-1 | 39-36 | 3 | 36,711 | Mark Gubicza | Jerry Reuss | Mark Gubicza | Jerry Reuss | Jerry Gleaton | 333 | 294 | 39 |
| 1988-06-28 | vs CHA | 76 | L 3-4 | 39-37 | 3 | 23,060 | Rick Anderson | Bill Long | Bill Long | Gene Garber | Bobby Thigpen | 336 | 298 | 38 |
| 1988-06-29 | vs CHA | 77 | W 9-8 | 40-37 | 3 | 26,333 | Floyd Bannister | Melido Perez | Floyd Bannister | Melido Perez | Steve Farr | 345 | 306 | 39 |
| 1988-07-01 | vs BOS | 78 | W 8-7 | 41-37 | 3 | 25,970 | Bret Saberhagen | Bruce Hurst | Jeff Montgomery | Steve Ellsworth | Steve Farr | 353 | 313 | 40 |
| 1988-07-02 | vs BOS | 79 | W 3-1 | 42-37 | 3 | 37,098 | Charlie Leibrandt | Oil Can Boyd | Charlie Leibrandt | Oil Can Boyd | Steve Farr | 356 | 314 | 42 |
| 1988-07-03 | vs BOS | 80 | W 3-2 | 43-37 | 3 | 36,220 | Mark Gubicza | Mike Smithson | Jeff Montgomery | Lee Smith | Steve Farr | 359 | 316 | 43 |
| 1988-07-04 | vs BOS | 81 | L 2-9 | 43-38 | 3 | 40,804 | Ted Power | Roger Clemens | Roger Clemens | Ted Power | | 361 | 325 | 36 |
| 1988-07-05 | vs MIL | 82 | L 1-3 | 43-39 | 3 | 22,761 | Floyd Bannister | Mike Birkbeck | Mike Birkbeck | Floyd Bannister | Dan Plesac | 362 | 328 | 34 |
| 1988-07-06 | vs MIL | 83 | L 2-4 | 43-40 | 3 | 24,477 | Bret Saberhagen | Tom Filer | Tom Filer | Bret Saberhagen | Dan Plesac | 364 | 332 | 32 |
| 1988-07-07 | vs MIL | 84 | W 7-3 | 44-40 | 3 | 33,559 | Charlie Leibrandt | Chris Bosio | Charlie Leibrandt | Chris Bosio | | 371 | 335 | 36 |
| 1988-07-08 | @ NYA | 85 | W 4-0 | 45-40 | 3 | 34,038 | Mark Gubicza | John Candelaria | Mark Gubicza | John Candelaria | | 375 | 335 | 40 |
| 1988-07-09 | @ NYA | 86 | L 3-5 | 45-41 | 3 | 36,557 | Ted Power | Rick Rhoden | Rick Rhoden | Ted Power | Charles Hudson | 378 | 340 | 38 |
| 1988-07-10 | @ NYA | 87 | W 5-3 | 46-41 | 3 | 55,318 | Floyd Bannister | Tommy John | Rick Anderson | Tim Stoddard | Steve Farr | 383 | 343 | 40 |
| 1988-07-15 | @ BOS | 88 | L 1-3 | 46-43 | 3 | 0 | Bret Saberhagen | Roger Clemens | Roger Clemens | Bret Saberhagen | | 384 | 346 | 38 |
| 1988-07-15 | @ BOS | 89 | L 4-7 | 46-43 | 3 | 35,412 | Charlie Leibrandt | Mike Smithson | Mike Smithson | Charlie Leibrandt | Lee Smith | 388 | 353 | 35 |
| 1988-07-16 | @ BOS | 90 | L 6-7 | 46-44 | 3 | 34,466 | Mark Gubicza | Oil Can Boyd | Lee Smith | Steve Farr | | 394 | 360 | 34 |
| 1988-07-17 | @ BOS | 91 | L 8-10 | 46-45 | 3 | 34,181 | Ted Power | Wes Gardner | Wes Gardner | Ted Power | | 402 | 370 | 32 |
| 1988-07-18 | @ MIL | 92 | L 1-6 | 46-46 | 3 | 21,832 | Floyd Bannister | Mike Birkbeck | Mike Birkbeck | Floyd Bannister | | 403 | 376 | 27 |
| 1988-07-19 | @ MIL | 93 | L 1-3 | 46-47 | 3 | 20,862 | Bret Saberhagen | Bill Wegman | Bill Wegman | Bret Saberhagen | Dan Plesac | 404 | 379 | 25 |
| 1988-07-20 | @ MIL | 94 | W 4-0 | 47-47 | 3 | 35,625 | Charlie Leibrandt | Teddy Higuera | Jeff Montgomery | Tom Filer | | 408 | 379 | 29 |
| 1988-07-21 | vs NYA | 95 | W 6-5 | 48-47 | 3 | 41,040 | Mark Gubicza | Rick Rhoden | Steve Farr | Cecilio Guante | | 414 | 384 | 30 |
| 1988-07-22 | vs NYA | 96 | L 8-9 | 48-48 | 3 | 40,011 | Ted Power | Tommy John | Neil Allen | Israel Sanchez | Dave Righetti | 422 | 393 | 29 |
| 1988-07-23 | vs NYA | 97 | W 6-5 | 49-48 | 3 | 41,377 | Floyd Bannister | Ron Guidry | Rick Anderson | Dave Righetti | Steve Farr | 428 | 398 | 30 |
| 1988-07-24 | vs NYA | 98 | L 8-10 | 49-49 | 3 | 38,591 | Bret Saberhagen | Richard Dotson | Neil Allen | Bret Saberhagen | Dave Righetti | 436 | 408 | 28 |
| 1988-07-26 | @ DET | 99 | L 1-2 | 49-50 | 3 | 27,255 | Charlie Leibrandt | Jack Morris | Mike Henneman | Jeff Montgomery | | 437 | 410 | 27 |
| 1988-07-27 | @ DET | 100 | L 1-3 | 49-51 | 3 | 26,288 | Mark Gubicza | Doyle Alexander | Doyle Alexander | Mark Gubicza | Mike Henneman | 438 | 413 | 25 |
| 1988-07-28 | @ DET | 101 | L 1-7 | 49-52 | 4 | 27,781 | Rick Anderson | Jeff Robinson | Jeff Robinson | Rick Anderson | | 439 | 420 | 19 |
| 1988-07-29 | @ BAL | 102 | W 6-2 | 50-52 | 4 | 24,795 | Bret Saberhagen | Jeff Ballard | Bret Saberhagen | Jeff Ballard | | 445 | 422 | 23 |
| 1988-07-30 | @ BAL | 103 | W 8-7 | 51-52 | 4 | 38,540 | Israel Sanchez | Jay Tibbs | Ted Power | Jay Tibbs | Steve Farr | 453 | 429 | 24 |
| 1988-07-31 | @ BAL | 104 | W 4-1 | 52-52 | 4 | 21,695 | Charlie Leibrandt | Jose Bautista | Charlie Leibrandt | Jose Bautista | | 457 | 430 | 27 |
| 1988-08-01 | vs DET | 105 | W 5-3 | 53-52 | 4 | 39,161 | Mark Gubicza | Doyle Alexander | Mark Gubicza | Doyle Alexander | Steve Farr | 462 | 433 | 29 |
| 1988-08-02 | vs DET | 106 | L 0-1 | 53-53 | 4 | 29,162 | Floyd Bannister | Jeff Robinson | Jeff Robinson | Floyd Bannister | Mike Henneman | 462 | 434 | 28 |
| 1988-08-03 | vs DET | 107 | W 2-1 | 54-53 | 4 | 27,467 | Bret Saberhagen | Frank Tanana | Bret Saberhagen | Frank Tanana | | 464 | 435 | 29 |
| 1988-08-05 | @ TOR | 108 | L 6-7 | 54-54 | 4 | 31,357 | Charlie Leibrandt | Jimmy Key | Duane Ward | Ted Power | Tom Henke | 470 | 442 | 28 |
| 1988-08-06 | @ TOR | 109 | W 11-1 | 55-54 | 4 | 34,411 | Mark Gubicza | Dave Stieb | Mark Gubicza | Dave Stieb | | 481 | 443 | 38 |
| 1988-08-07 | @ TOR | 110 | W 5-1 | 56-54 | 4 | 37,304 | Floyd Bannister | Jim Clancy | Floyd Bannister | Jim Clancy | | 486 | 444 | 42 |
| 1988-08-08 | @ TOR | 111 | L 1-5 | 56-55 | 4 | 32,234 | Bret Saberhagen | Jeff Musselman | Jeff Musselman | Bret Saberhagen | Tom Henke | 487 | 449 | 38 |
| 1988-08-09 | vs BAL | 112 | W 5-4 | 57-55 | 3 | 24,005 | Luis Aquino | Dave J. Schmidt | Israel Sanchez | Tom Niedenfuer | | 492 | 453 | 39 |
| 1988-08-10 | vs BAL | 113 | W 4-3 | 58-55 | 3 | 28,579 | Charlie Leibrandt | Jose Bautista | Jeff Montgomery | Jose Bautista | Steve Farr | 496 | 456 | 40 |
| 1988-08-11 | vs BAL | 114 | W 6-5 | 59-55 | 3 | 33,920 | Mark Gubicza | Mike Morgan | Jeff Montgomery | Tom Niedenfuer | | 502 | 461 | 41 |
| 1988-08-12 | vs TOR | 115 | L 2-3 | 59-56 | 3 | 31,858 | Floyd Bannister | Jim Clancy | Jim Clancy | Floyd Bannister | Tom Henke | 504 | 464 | 40 |
| 1988-08-13 | vs TOR | 116 | L 0-2 | 59-57 | 3 | 40,204 | Bret Saberhagen | Jeff Musselman | Jeff Musselman | Bret Saberhagen | Duane Ward | 504 | 466 | 38 |
| 1988-08-14 | vs TOR | 117 | W 6-0 | 60-57 | 3 | 27,262 | Luis Aquino | Mike Flanagan | Luis Aquino | Mike Flanagan | | 510 | 466 | 44 |
| 1988-08-15 | vs TEX | 118 | W 12-3 | 61-57 | 3 | 33,104 | Charlie Leibrandt | Paul Kilgus | Charlie Leibrandt | Paul Kilgus | | 522 | 469 | 53 |
| 1988-08-16 | vs TEX | 119 | L 4-5 | 61-58 | 3 | 24,729 | Mark Gubicza | Charlie Hough | Charlie Hough | Mark Gubicza | Mitch Williams | 526 | 474 | 52 |
| 1988-08-17 | vs TEX | 120 | W 9-6 | 62-58 | 3 | 25,720 | Floyd Bannister | Jose Guzman | Jeff Montgomery | Jose Guzman | Steve Farr | 535 | 480 | 55 |
| 1988-08-19 | @ CLE | 121 | L 2-4 | 62-59 | 3 | 13,098 | Bret Saberhagen | Tom Candiotti | Tom Candiotti | Bret Saberhagen | Doug Jones | 537 | 484 | 53 |
| 1988-08-20 | @ CLE | 122 | W 4-2 | 63-59 | 3 | 17,047 | Charlie Leibrandt | Greg Swindell | Charlie Leibrandt | Greg Swindell | Steve Farr | 541 | 486 | 55 |
| 1988-08-21 | @ CLE | 123 | W 3-1 | 64-59 | 3 | 17,949 | Mark Gubicza | Buddy Black | Mark Gubicza | Rod Nichols | | 544 | 487 | 57 |
| 1988-08-22 | @ TEX | 124 | L 5-9 | 64-60 | 3 | 16,928 | Floyd Bannister | Jose Guzman | Jose Guzman | Floyd Bannister | Ed Vande Berg | 549 | 496 | 53 |
| 1988-08-23 | @ TEX | 125 | W 11-7 | 65-60 | 3 | 18,051 | Luis Aquino | Jeff Russell | Steve Farr | Dale Mohorcic | | 560 | 503 | 57 |
| 1988-08-24 | @ TEX | 126 | L 4-7 | 65-61 | 3 | 17,384 | Bret Saberhagen | Bobby Witt | Bobby Witt | Jerry Gleaton | | 564 | 510 | 54 |
| 1988-08-26 | vs MIN | 127 | W 4-3 | 66-61 | 3 | 41,097 | Charlie Leibrandt | Frank Viola | Charlie Leibrandt | Frank Viola | | 568 | 513 | 55 |
| 1988-08-27 | vs MIN | 128 | W 4-1 | 67-61 | 3 | 38,326 | Mark Gubicza | Bert Blyleven | Mark Gubicza | Bert Blyleven | | 572 | 514 | 58 |
| 1988-08-28 | vs MIN | 129 | W 12-3 | 68-61 | 3 | 27,578 | Luis Aquino | Allan Anderson | Jeff Montgomery | Allan Anderson | | 584 | 517 | 67 |
| 1988-08-29 | vs CLE | 130 | W 6-3 | 69-61 | 3 | 29,002 | Bret Saberhagen | Rich Yett | Bret Saberhagen | Scott Bailes | Steve Farr | 590 | 520 | 70 |
| 1988-08-30 | vs CLE | 131 | L 1-4 | 69-62 | 3 | 23,437 | Ted Power | Tom Candiotti | Tom Candiotti | Ted Power | Brad Havens | 591 | 524 | 67 |
| 1988-08-31 | vs CLE | 132 | W 1-0 | 70-62 | 3 | 20,615 | Charlie Leibrandt | Greg Swindell | Charlie Leibrandt | Greg Swindell | | 592 | 524 | 68 |
| 1988-09-01 | @ MIN | 133 | W 5-2 | 71-62 | 3 | 28,865 | Mark Gubicza | Bert Blyleven | Mark Gubicza | Bert Blyleven | | 597 | 526 | 71 |
| 1988-09-02 | @ MIN | 134 | L 3-6 | 71-63 | 3 | 36,291 | Floyd Bannister | Allan Anderson | Allan Anderson | Floyd Bannister | Jeff Reardon | 600 | 532 | 68 |
| 1988-09-03 | @ MIN | 135 | L 6-8 | 71-64 | 3 | 47,658 | Bret Saberhagen | Freddie Toliver | Mark Portugal | Jerry Gleaton | Jeff Reardon | 606 | 540 | 66 |
| 1988-09-04 | @ MIN | 136 | W 3-2 | 72-64 | 3 | 40,967 | Luis Aquino | Les Straker | Israel Sanchez | Les Straker | Steve Farr | 609 | 542 | 67 |
| 1988-09-05 | vs CAL | 137 | L 2-4 | 72-65 | 3 | 25,855 | Charlie Leibrandt | Willie Fraser | Willie Fraser | Charlie Leibrandt | Bryan Harvey | 611 | 546 | 65 |
| 1988-09-06 | vs CAL | 138 | W 3-2 | 73-65 | 3 | 16,645 | Mark Gubicza | Terry Clark | Steve Farr | Greg Minton | | 614 | 548 | 66 |
| 1988-09-07 | vs CAL | 139 | W 4-2 | 74-65 | 3 | 16,600 | Floyd Bannister | Chuck Finley | Floyd Bannister | Chuck Finley | Steve Farr | 618 | 550 | 68 |
| 1988-09-08 | vs OAK | 140 | L 1-5 | 74-66 | 3 | 29,167 | Bret Saberhagen | Curt Young | Curt Young | Bret Saberhagen | Dennis Eckersley | 619 | 555 | 64 |
| 1988-09-09 | vs OAK | 141 | L 6-14 | 74-67 | 3 | 26,675 | Jose De Jesus | Dave Stewart | Dave Stewart | Jose De Jesus | Rick Honeycutt | 625 | 569 | 56 |
| 1988-09-10 | vs OAK | 142 | W 9-4 | 75-67 | 3 | 37,983 | Charlie Leibrandt | Storm Davis | Charlie Leibrandt | Storm Davis | | 634 | 573 | 61 |
| 1988-09-11 | vs OAK | 143 | L 7-8 | 75-68 | 3 | 28,953 | Mark Gubicza | Bob Welch | Dennis Eckersley | Steve Farr | | 641 | 581 | 60 |
| 1988-09-13 | @ CAL | 144 | W 4-3 | 76-68 | 3 | 22,522 | Bret Saberhagen | Chuck Finley | Bret Saberhagen | Chuck Finley | Steve Farr | 645 | 584 | 61 |
| 1988-09-14 | @ CAL | 145 | W 4-2 | 77-68 | 3 | 21,550 | Floyd Bannister | Mike Witt | Floyd Bannister | Mike Witt | Steve Farr | 649 | 586 | 63 |
| 1988-09-15 | @ CAL | 146 | W 2-1 | 78-68 | 3 | 22,638 | Charlie Leibrandt | Dan Petry | Charlie Leibrandt | Dan Petry | | 651 | 587 | 64 |
| 1988-09-16 | @ OAK | 147 | W 3-0 | 79-68 | 3 | 33,881 | Mark Gubicza | Bob Welch | Mark Gubicza | Bob Welch | | 654 | 587 | 67 |
| 1988-09-17 | @ OAK | 148 | L 2-3 | 79-69 | 3 | 43,875 | Tom Gordon | Dave Otto | Eric Plunk | Tom Gordon | Dennis Eckersley | 656 | 590 | 66 |
| 1988-09-18 | @ OAK | 149 | L 2-3 | 79-70 | 3 | 35,515 | Bret Saberhagen | Curt Young | Greg Cadaret | Steve Farr | | 658 | 593 | 65 |
| 1988-09-19 | @ SEA | 150 | L 0-4 | 79-71 | 3 | 6,557 | Floyd Bannister | Mark Langston | Mark Langston | Floyd Bannister | | 658 | 597 | 61 |
| 1988-09-20 | @ SEA | 151 | L 10-11 | 79-72 | 3 | 6,916 | Charlie Leibrandt | Terry Taylor | Mike Schooler | Jerry Gleaton | | 668 | 608 | 60 |
| 1988-09-21 | @ SEA | 152 | W 5-4 | 80-72 | 3 | 7,382 | Mark Gubicza | Erik Hanson | Mark Gubicza | Michael Jackson | Israel Sanchez | 673 | 612 | 61 |
| 1988-09-23 | @ CHA | 153 | L 0-2 | 80-73 | 3 | 11,548 | Bret Saberhagen | Jerry Reuss | Jerry Reuss | Bret Saberhagen | Bobby Thigpen | 673 | 614 | 59 |
| 1988-09-24 | @ CHA | 154 | W 6-2 | 81-73 | 3 | 15,790 | Floyd Bannister | Adam Peterson | Floyd Bannister | Adam Peterson | | 679 | 616 | 63 |
| 1988-09-25 | @ CHA | 155 | L 5-6 | 81-74 | 3 | 10,608 | Charlie Leibrandt | Ravelo Manzanillo | Barry Jones | Israel Sanchez | | 684 | 622 | 62 |
| 1988-09-26 | vs SEA | 156 | W 5-0 | 82-74 | 3 | 19,122 | Mark Gubicza | Bill Swift | Mark Gubicza | Bill Swift | | 689 | 622 | 67 |
| 1988-09-27 | vs SEA | 157 | L 3-10 | 82-75 | 3 | 17,463 | Tom Gordon | Erik Hanson | Erik Hanson | Tom Gordon | Michael Jackson | 692 | 632 | 60 |
| 1988-09-29 | vs CHA | 158 | W 7-6 | 83-75 | 3 | 18,850 | Floyd Bannister | Adam Peterson | Israel Sanchez | Donn Pall | | 699 | 638 | 61 |
| 1988-09-30 | vs CHA | 159 | W 4-2 | 84-75 | 3 | 20,785 | Charlie Leibrandt | Ravelo Manzanillo | Charlie Leibrandt | Ravelo Manzanillo | | 703 | 640 | 63 |
| 1988-10-01 | vs CHA | 160 | L 0-3 | 84-76 | 3 | 28,040 | Mark Gubicza | Melido Perez | Melido Perez | Mark Gubicza | | 703 | 643 | 60 |
| 1988-10-02 | vs CHA | 161 | L 1-5 | 84-77 | 3 | 19,951 | Bret Saberhagen | Shawn Hillegas | Shawn Hillegas | Bret Saberhagen | Tom McCarthy | 704 | 648 | 56 |