| 1988-04-04 | @ BOS | 1 | W 5-3 | 1-0 | 1 | 34,781 | Jack Morris | Roger Clemens | Jack Morris | Lee Smith | Mike Henneman | 5 | 3 | 2 |
| 1988-04-06 | @ BOS | 2 | L 5-6 | 1-1 | 6 | 16,965 | Doyle Alexander | Bruce Hurst | Dennis Lamp | Guillermo Hernandez | Lee Smith | 10 | 9 | 1 |
| 1988-04-07 | @ BOS | 3 | W 11-6 | 2-1 | 4 | 13,807 | Frank Tanana | Steve Ellsworth | Frank Tanana | Steve Ellsworth | | 21 | 15 | 6 |
| 1988-04-08 | @ KCA | 4 | L 2-3 | 2-2 | 5 | 26,159 | Jeff Robinson | Floyd Bannister | Floyd Bannister | Jeff Robinson | Gene Garber | 23 | 18 | 5 |
| 1988-04-09 | @ KCA | 5 | W 11-4 | 3-2 | 4 | 23,418 | Jack Morris | Bret Saberhagen | Jack Morris | Buddy Black | | 34 | 22 | 12 |
| 1988-04-10 | @ KCA | 6 | L 1-8 | 3-3 | 4 | 26,305 | Doyle Alexander | Charlie Leibrandt | Charlie Leibrandt | Doyle Alexander | | 35 | 30 | 5 |
| 1988-04-12 | vs TEX | 7 | W 4-1 | 4-3 | 4 | 51,504 | Frank Tanana | Bobby Witt | Frank Tanana | Bobby Witt | Mike Henneman | 39 | 31 | 8 |
| 1988-04-14 | vs TEX | 8 | L 1-2 | 4-4 | 4 | 11,899 | Jack Morris | Jose Guzman | Jose Guzman | Jack Morris | Mitch Williams | 40 | 33 | 7 |
| 1988-04-16 | vs KCA | 9 | W 4-2 | 5-4 | 3 | 18,480 | Doyle Alexander | Charlie Leibrandt | Doyle Alexander | Charlie Leibrandt | Mike Henneman | 44 | 35 | 9 |
| 1988-04-17 | vs KCA | 10 | W 8-6 | 6-4 | 3 | 18,292 | Jeff Robinson | Mark Gubicza | Jeff Robinson | Mark Gubicza | Mike Henneman | 52 | 41 | 11 |
| 1988-04-18 | vs KCA | 11 | W 4-2 | 7-4 | 3 | 11,001 | Frank Tanana | Floyd Bannister | Frank Tanana | Floyd Bannister | Mike Henneman | 56 | 43 | 13 |
| 1988-04-19 | vs BOS | 12 | L 3-7 | 7-5 | 4 | 11,920 | Jack Morris | Roger Clemens | Roger Clemens | Jack Morris | | 59 | 50 | 9 |
| 1988-04-21 | vs BOS | 13 | L 3-12 | 7-6 | 4 | 13,862 | Jeff Robinson | Steve Ellsworth | Steve Ellsworth | Jeff Robinson | | 62 | 62 | 0 |
| 1988-04-22 | @ TEX | 14 | W 5-3 | 8-6 | 4 | 23,443 | Doyle Alexander | Paul Kilgus | Doyle Alexander | Paul Kilgus | Mike Henneman | 67 | 65 | 2 |
| 1988-04-23 | @ TEX | 15 | W 7-6 | 9-6 | 4 | 34,890 | Frank Tanana | Bobby Witt | Frank Tanana | Bobby Witt | Mike Henneman | 74 | 71 | 3 |
| 1988-04-24 | @ TEX | 16 | L 2-4 | 9-7 | 4 | 29,543 | Jack Morris | Charlie Hough | Charlie Hough | Jack Morris | Mitch Williams | 76 | 75 | 1 |
| 1988-04-26 | vs CAL | 17 | W 6-0 | 10-7 | 4 | 11,973 | Jeff Robinson | Mike Witt | Jeff Robinson | Mike Witt | | 82 | 75 | 7 |
| 1988-04-27 | vs CAL | 18 | L 3-4 | 10-8 | 4 | 10,927 | Doyle Alexander | Willie Fraser | Willie Fraser | Doyle Alexander | Donnie Moore | 85 | 79 | 6 |
| 1988-04-28 | vs CAL | 19 | W 2-1 | 11-8 | 4 | 10,976 | Frank Tanana | Kirk McCaskill | Frank Tanana | Kirk McCaskill | Mike Henneman | 87 | 80 | 7 |
| 1988-04-29 | vs SEA | 20 | W 9-6 | 12-8 | 4 | 13,757 | Jack Morris | Mark Langston | Guillermo Hernandez | Mark Langston | Don Heinkel | 96 | 86 | 10 |
| 1988-04-30 | vs SEA | 21 | W 4-3 | 13-8 | 4 | 17,505 | Walt Terrell | Bill Swift | Paul Gibson | Michael Jackson | | 100 | 89 | 11 |
| 1988-05-01 | vs SEA | 22 | W 3-2 | 14-8 | 4 | 28,432 | Jeff Robinson | Mike Moore | Jeff Robinson | Mike Moore | Guillermo Hernandez | 103 | 91 | 12 |
| 1988-05-02 | vs OAK | 23 | L 2-4 | 14-9 | 4 | 15,856 | Doyle Alexander | Curt Young | Curt Young | Mike Henneman | Dennis Eckersley | 105 | 95 | 10 |
| 1988-05-03 | vs OAK | 24 | L 2-8 | 14-10 | 4 | 20,221 | Frank Tanana | Dave Stewart | Dave Stewart | Frank Tanana | | 107 | 103 | 4 |
| 1988-05-04 | @ CAL | 25 | W 1-0 | 15-10 | 3 | 26,020 | Jack Morris | Dan Petry | Jack Morris | Dan Petry | | 108 | 103 | 5 |
| 1988-05-05 | @ CAL | 26 | W 8-5 | 16-10 | 3 | 23,821 | Walt Terrell | Chuck Finley | Guillermo Hernandez | Chuck Finley | Mike Henneman | 116 | 108 | 8 |
| 1988-05-06 | @ SEA | 27 | W 8-4 | 17-10 | 3 | 16,667 | Jeff Robinson | Mike Moore | Jeff Robinson | Dennis Powell | Mike Henneman | 124 | 112 | 12 |
| 1988-05-07 | @ SEA | 28 | L 6-7 | 17-11 | 3 | 27,019 | Doyle Alexander | Steve Trout | Dennis Powell | Paul Gibson | Bill Wilkinson | 130 | 119 | 11 |
| 1988-05-08 | @ SEA | 29 | W 9-3 | 18-11 | 2 | 12,695 | Frank Tanana | Mike Campbell | Frank Tanana | Mike Campbell | | 139 | 122 | 17 |
| 1988-05-09 | @ OAK | 30 | L 1-3 | 18-12 | 3 | 35,300 | Jack Morris | Bob Welch | Bob Welch | Jack Morris | Dennis Eckersley | 140 | 125 | 15 |
| 1988-05-10 | @ OAK | 31 | W 8-2 | 19-12 | 2 | 23,341 | Walt Terrell | Curt Young | Walt Terrell | Curt Young | | 148 | 127 | 21 |
| 1988-05-11 | @ OAK | 32 | W 8-4 | 20-12 | 2 | 26,860 | Jeff Robinson | Storm Davis | Guillermo Hernandez | Dennis Eckersley | | 156 | 131 | 25 |
| 1988-05-13 | vs MIN | 33 | W 7-0 | 21-12 | 2 | 24,147 | Doyle Alexander | Allan Anderson | Doyle Alexander | Allan Anderson | | 163 | 131 | 32 |
| 1988-05-14 | vs MIN | 34 | L 0-7 | 21-13 | 3 | 35,429 | Frank Tanana | Les Straker | Les Straker | Frank Tanana | | 163 | 138 | 25 |
| 1988-05-15 | vs MIN | 35 | L 2-10 | 21-14 | 3 | 29,568 | Jack Morris | Frank Viola | Frank Viola | Jack Morris | | 165 | 148 | 17 |
| 1988-05-16 | @ MIL | 36 | L 1-3 | 21-15 | 3 | 8,976 | Walt Terrell | Chris Bosio | Chris Bosio | Walt Terrell | Dan Plesac | 166 | 151 | 15 |
| 1988-05-17 | @ MIL | 37 | W 8-4 | 22-15 | 3 | 11,493 | Paul Gibson | Juan Nieves | Paul Gibson | Juan Nieves | | 174 | 155 | 19 |
| 1988-05-18 | @ MIL | 38 | W 3-1 | 23-15 | 3 | 23,577 | Doyle Alexander | Teddy Higuera | Doyle Alexander | Teddy Higuera | | 177 | 156 | 21 |
| 1988-05-20 | @ CHA | 39 | W 14-6 | 24-15 | 3 | 19,308 | Frank Tanana | Jerry Reuss | Frank Tanana | Jerry Reuss | | 191 | 162 | 29 |
| 1988-05-21 | @ CHA | 40 | W 3-1 | 25-15 | 3 | 21,693 | Jack Morris | Jeff Bittiger | Jack Morris | Jeff Bittiger | Mike Henneman | 194 | 163 | 31 |
| 1988-05-22 | @ CHA | 41 | W 3-1 | 26-15 | 3 | 17,628 | Walt Terrell | Jack McDowell | Walt Terrell | Jack McDowell | | 197 | 164 | 33 |
| 1988-05-24 | vs MIL | 42 | L 0-7 | 26-16 | 3 | 17,268 | Doyle Alexander | Tom Filer | Tom Filer | Doyle Alexander | | 197 | 171 | 26 |
| 1988-05-25 | vs MIL | 43 | W 4-3 | 27-16 | 3 | 17,806 | Jeff Robinson | Juan Nieves | Jeff Robinson | Juan Nieves | Guillermo Hernandez | 201 | 174 | 27 |
| 1988-05-26 | vs MIL | 44 | W 4-3 | 28-16 | 3 | 16,005 | Frank Tanana | Chris Bosio | Frank Tanana | Chris Bosio | Eric King | 205 | 177 | 28 |
| 1988-05-27 | @ MIN | 45 | L 1-7 | 28-17 | 3 | 45,281 | Jack Morris | Frank Viola | Frank Viola | Jack Morris | | 206 | 184 | 22 |
| 1988-05-28 | @ MIN | 46 | L 2-5 | 28-18 | 3 | 38,403 | Walt Terrell | Les Straker | Keith Atherton | Walt Terrell | Jeff Reardon | 208 | 189 | 19 |
| 1988-05-29 | @ MIN | 47 | L 3-6 | 28-19 | 3 | 43,727 | Doyle Alexander | Allan Anderson | Allan Anderson | Doyle Alexander | Jeff Reardon | 211 | 195 | 16 |
| 1988-05-31 | vs CHA | 48 | L 1-10 | 28-20 | 3 | 13,223 | Frank Tanana | Jerry Reuss | Jerry Reuss | Frank Tanana | | 212 | 205 | 7 |
| 1988-06-01 | vs CHA | 49 | W 9-3 | 29-20 | 3 | 13,763 | Jack Morris | Jeff Bittiger | Jack Morris | Jeff Bittiger | Guillermo Hernandez | 221 | 208 | 13 |
| 1988-06-03 | vs CLE | 50 | L 3-6 | 29-21 | 3 | 25,230 | Walt Terrell | Rich Yett | Rich Yett | Walt Terrell | Dan Schatzeder | 224 | 214 | 10 |
| 1988-06-04 | vs CLE | 51 | W 5-2 | 30-21 | 3 | 32,391 | Doyle Alexander | Tom Candiotti | Doyle Alexander | Tom Candiotti | | 229 | 216 | 13 |
| 1988-06-05 | vs CLE | 52 | W 6-2 | 31-21 | 3 | 31,665 | Jeff Robinson | Greg Swindell | Jeff Robinson | Greg Swindell | | 235 | 218 | 17 |
| 1988-06-06 | @ BAL | 53 | L 2-5 | 31-22 | 3 | 22,317 | Jack Morris | Jeff Ballard | Jeff Ballard | Jack Morris | Tom Niedenfuer | 237 | 223 | 14 |
| 1988-06-07 | @ BAL | 54 | L 3-4 | 31-23 | 3 | 23,641 | Frank Tanana | Jay Tibbs | Doug Sisk | Frank Tanana | | 240 | 227 | 13 |
| 1988-06-08 | @ BAL | 55 | W 12-4 | 32-23 | 3 | 17,120 | Walt Terrell | Jose Bautista | Paul Gibson | Jose Bautista | | 252 | 231 | 21 |
| 1988-06-09 | @ CLE | 56 | W 6-2 | 33-23 | 3 | 17,375 | Doyle Alexander | Tom Candiotti | Mike Henneman | Tom Candiotti | | 258 | 233 | 25 |
| 1988-06-10 | @ CLE | 57 | W 2-1 | 34-23 | 3 | 71,188 | Jeff Robinson | Greg Swindell | Jeff Robinson | Greg Swindell | Mike Henneman | 260 | 234 | 26 |
| 1988-06-11 | @ CLE | 58 | W 11-3 | 35-23 | 2 | 26,978 | Jack Morris | John Farrell | Jack Morris | John Farrell | | 271 | 237 | 34 |
| 1988-06-12 | @ CLE | 59 | W 5-4 | 36-23 | 2 | 41,345 | Frank Tanana | Scott Bailes | Frank Tanana | Scott Bailes | Mike Henneman | 276 | 241 | 35 |
| 1988-06-13 | vs BAL | 60 | L 4-6 | 36-24 | 2 | 17,126 | Walt Terrell | Jose Bautista | Tom Niedenfuer | Guillermo Hernandez | | 280 | 247 | 33 |
| 1988-06-14 | vs BAL | 61 | W 9-3 | 37-24 | 2 | 15,128 | Doyle Alexander | Dickie Noles | Doyle Alexander | Dickie Noles | | 289 | 250 | 39 |
| 1988-06-15 | vs BAL | 62 | W 1-0 | 38-24 | 2 | 14,771 | Jeff Robinson | Mike Boddicker | Jeff Robinson | Mike Boddicker | | 290 | 250 | 40 |
| 1988-06-16 | vs TOR | 63 | L 5-13 | 38-25 | 2 | 22,927 | Jack Morris | Mike Flanagan | Mike Flanagan | Jack Morris | | 295 | 263 | 32 |
| 1988-06-17 | vs TOR | 64 | W 12-5 | 39-25 | 2 | 36,274 | Frank Tanana | John Cerutti | Guillermo Hernandez | David Wells | | 307 | 268 | 39 |
| 1988-06-18 | vs TOR | 65 | W 6-1 | 40-25 | 2 | 42,186 | Walt Terrell | Jim Clancy | Walt Terrell | Jim Clancy | | 313 | 269 | 44 |
| 1988-06-19 | vs TOR | 66 | L 4-6 | 40-26 | 2 | 35,639 | Doyle Alexander | Todd Stottlemyre | Duane Ward | Mike Henneman | Tom Henke | 317 | 275 | 42 |
| 1988-06-20 | vs NYA | 67 | W 2-1 | 41-26 | 1 | 33,660 | Jeff Robinson | Tommy John | Guillermo Hernandez | Cecilio Guante | | 319 | 276 | 43 |
| 1988-06-21 | vs NYA | 68 | W 7-6 | 42-26 | 1 | 26,535 | Jack Morris | Al Leiter | Eric King | Cecilio Guante | | 326 | 282 | 44 |
| 1988-06-22 | vs NYA | 69 | W 3-2 | 43-26 | 1 | 33,014 | Frank Tanana | John Candelaria | Mike Henneman | Charles Hudson | | 329 | 284 | 45 |
| 1988-06-24 | @ TOR | 70 | L 3-6 | 43-27 | 1 | 40,533 | Walt Terrell | Todd Stottlemyre | Todd Stottlemyre | Walt Terrell | Tom Henke | 332 | 290 | 42 |
| 1988-06-25 | @ TOR | 71 | W 7-2 | 44-27 | 1 | 45,091 | Doyle Alexander | Dave Stieb | Doyle Alexander | Dave Stieb | | 339 | 292 | 47 |
| 1988-06-26 | @ TOR | 72 | L 1-4 | 44-28 | 1 | 45,278 | Jeff Robinson | Mike Flanagan | Mike Flanagan | Jeff Robinson | Tom Henke | 340 | 296 | 44 |
| 1988-06-27 | @ NYA | 73 | W 6-3 | 45-28 | 1 | 26,862 | Jack Morris | John Candelaria | Jack Morris | John Candelaria | Mike Henneman | 346 | 299 | 47 |
| 1988-06-28 | @ NYA | 74 | W 6-1 | 46-28 | 1 | 37,103 | Frank Tanana | Rick Rhoden | Frank Tanana | Rick Rhoden | | 352 | 300 | 52 |
| 1988-06-29 | @ NYA | 75 | L 3-7 | 46-29 | 1 | 33,064 | Walt Terrell | Richard Dotson | Steve Shields | Walt Terrell | | 355 | 307 | 48 |
| 1988-07-01 | vs CAL | 76 | W 11-0 | 47-29 | 1 | 23,762 | Doyle Alexander | Mike Witt | Doyle Alexander | Mike Witt | | 366 | 307 | 59 |
| 1988-07-02 | vs CAL | 77 | W 6-1 | 48-29 | 1 | 30,548 | Jeff Robinson | Willie Fraser | Jeff Robinson | Willie Fraser | | 372 | 308 | 64 |
| 1988-07-03 | vs CAL | 78 | L 4-10 | 48-30 | 1 | 32,176 | Jack Morris | Kirk McCaskill | Kirk McCaskill | Jack Morris | | 376 | 318 | 58 |
| 1988-07-04 | vs SEA | 79 | W 5-3 | 49-30 | 1 | 19,710 | Frank Tanana | Mike Moore | Mike Henneman | Rod Scurry | Eric King | 381 | 321 | 60 |
| 1988-07-05 | vs SEA | 80 | L 4-5 | 49-31 | 1 | 17,185 | Walt Terrell | Steve Trout | Steve Trout | Walt Terrell | Mike Schooler | 385 | 326 | 59 |
| 1988-07-06 | vs SEA | 81 | W 7-6 | 50-31 | 1 | 18,298 | Doyle Alexander | Mark Langston | Mike Henneman | Mike Schooler | | 392 | 332 | 60 |
| 1988-07-07 | vs OAK | 82 | W 8-1 | 51-31 | 1 | 28,061 | Jeff Robinson | Curt Young | Jeff Robinson | Curt Young | | 400 | 333 | 67 |
| 1988-07-08 | vs OAK | 83 | L 2-3 | 51-32 | 1 | 37,498 | Eric King | Storm Davis | Storm Davis | Eric King | Dennis Eckersley | 402 | 336 | 66 |
| 1988-07-09 | vs OAK | 84 | W 4-3 | 52-32 | 1 | 43,016 | Frank Tanana | Bob Welch | Frank Tanana | Bob Welch | Guillermo Hernandez | 406 | 339 | 67 |
| 1988-07-10 | vs OAK | 85 | L 2-8 | 52-33 | 1 | 36,519 | Walt Terrell | Dave Stewart | Dave Stewart | Walt Terrell | | 408 | 347 | 61 |
| 1988-07-14 | @ CAL | 86 | L 0-2 | 52-34 | 1 | 30,165 | Jack Morris | Kirk McCaskill | Kirk McCaskill | Jack Morris | | 408 | 349 | 59 |
| 1988-07-15 | @ CAL | 87 | L 4-6 | 52-35 | 1 | 34,829 | Doyle Alexander | Mike Witt | Mike Witt | Doyle Alexander | Bryan Harvey | 412 | 355 | 57 |
| 1988-07-16 | @ CAL | 88 | W 10-1 | 53-35 | 1 | 30,082 | Jeff Robinson | Willie Fraser | Jeff Robinson | Willie Fraser | | 422 | 356 | 66 |
| 1988-07-17 | @ CAL | 89 | L 0-4 | 53-36 | 1 | 36,030 | Frank Tanana | Terry Clark | Terry Clark | Frank Tanana | | 422 | 360 | 62 |
| 1988-07-18 | @ SEA | 90 | W 12-3 | 54-36 | 1 | 13,613 | Walt Terrell | Steve Trout | Walt Terrell | Steve Trout | | 434 | 363 | 71 |
| 1988-07-19 | @ SEA | 91 | L 6-9 | 54-37 | 1 | 10,647 | Jack Morris | Mark Langston | Michael Jackson | Jack Morris | Mike Schooler | 440 | 372 | 68 |
| 1988-07-20 | @ SEA | 92 | W 12-5 | 55-37 | 1 | 10,959 | Doyle Alexander | Mike Moore | Doyle Alexander | Mike Moore | | 452 | 377 | 75 |
| 1988-07-22 | @ OAK | 93 | L 1-4 | 55-38 | 1 | 35,480 | Jeff Robinson | Storm Davis | Storm Davis | Jeff Robinson | Dennis Eckersley | 453 | 381 | 72 |
| 1988-07-23 | @ OAK | 94 | L 1-4 | 55-39 | 1 | 43,185 | Frank Tanana | Todd Burns | Todd Burns | Frank Tanana | Eric Plunk | 454 | 385 | 69 |
| 1988-07-24 | @ OAK | 95 | L 0-1 | 55-40 | 1 | 43,146 | Walt Terrell | Bob Welch | Bob Welch | Walt Terrell | | 454 | 386 | 68 |
| 1988-07-26 | vs KCA | 96 | W 2-1 | 56-40 | 2 | 27,255 | Jack Morris | Charlie Leibrandt | Mike Henneman | Jeff Montgomery | | 456 | 387 | 69 |
| 1988-07-27 | vs KCA | 97 | W 3-1 | 57-40 | 2 | 26,288 | Doyle Alexander | Mark Gubicza | Doyle Alexander | Mark Gubicza | Mike Henneman | 459 | 388 | 71 |
| 1988-07-28 | vs KCA | 98 | W 7-1 | 58-40 | 1 | 27,781 | Jeff Robinson | Rick Anderson | Jeff Robinson | Rick Anderson | | 466 | 389 | 77 |
| 1988-07-29 | vs TEX | 99 | W 3-2 | 59-41 | 1 | 0 | Frank Tanana | Paul Kilgus | Frank Tanana | Craig McMurtry | | 469 | 391 | 78 |
| 1988-07-29 | vs TEX | 100 | L 1-2 | 59-41 | 1 | 31,627 | Eric King | Bobby Witt | Bobby Witt | Guillermo Hernandez | | 470 | 393 | 77 |
| 1988-07-30 | vs TEX | 101 | W 3-0 | 60-41 | 1 | 36,972 | Walt Terrell | Charlie Hough | Walt Terrell | Charlie Hough | | 473 | 393 | 80 |
| 1988-07-31 | vs TEX | 102 | W 5-1 | 61-41 | 1 | 35,977 | Jack Morris | Jose Guzman | Jack Morris | Ed Vande Berg | | 478 | 394 | 84 |
| 1988-08-01 | @ KCA | 103 | L 3-5 | 61-42 | 1 | 39,161 | Doyle Alexander | Mark Gubicza | Mark Gubicza | Doyle Alexander | Steve Farr | 481 | 399 | 82 |
| 1988-08-02 | @ KCA | 104 | W 1-0 | 62-42 | 1 | 29,162 | Jeff Robinson | Floyd Bannister | Jeff Robinson | Floyd Bannister | Mike Henneman | 482 | 399 | 83 |
| 1988-08-03 | @ KCA | 105 | L 1-2 | 62-43 | 2 | 27,467 | Frank Tanana | Bret Saberhagen | Bret Saberhagen | Frank Tanana | | 483 | 401 | 82 |
| 1988-08-04 | vs BOS | 106 | W 11-6 | 63-43 | 1 | 40,980 | Walt Terrell | Roger Clemens | Walt Terrell | Roger Clemens | | 494 | 407 | 87 |
| 1988-08-05 | vs BOS | 107 | W 3-1 | 65-43 | 1 | 0 | Jack Morris | Mike Smithson | Jack Morris | Bob Stanley | Mike Henneman | 497 | 408 | 89 |
| 1988-08-05 | vs BOS | 108 | W 3-2 | 65-43 | 1 | 44,334 | Eric King | Mike Boddicker | Eric King | Mike Boddicker | Mike Henneman | 500 | 410 | 90 |
| 1988-08-06 | vs BOS | 109 | W 4-2 | 66-43 | 1 | 44,838 | Doyle Alexander | Wes Gardner | Doyle Alexander | Wes Gardner | | 504 | 412 | 92 |
| 1988-08-07 | vs BOS | 110 | L 0-3 | 66-44 | 1 | 41,623 | Jeff Robinson | Bruce Hurst | Bruce Hurst | Jeff Robinson | | 504 | 415 | 89 |
| 1988-08-08 | @ TEX | 111 | W 3-2 | 67-44 | 1 | 22,794 | Frank Tanana | Jeff Russell | Frank Tanana | Jeff Russell | Mike Henneman | 507 | 417 | 90 |
| 1988-08-09 | @ TEX | 112 | L 2-6 | 67-45 | 1 | 14,524 | Walt Terrell | Bobby Witt | Bobby Witt | Walt Terrell | | 509 | 423 | 86 |
| 1988-08-10 | @ TEX | 113 | W 2-1 | 68-45 | 1 | 15,550 | Jack Morris | Paul Kilgus | Jack Morris | Paul Kilgus | Guillermo Hernandez | 511 | 424 | 87 |
| 1988-08-12 | @ BOS | 114 | L 4-9 | 68-46 | 1 | 34,732 | Doyle Alexander | Bruce Hurst | Bruce Hurst | Doyle Alexander | Bob Stanley | 515 | 433 | 82 |
| 1988-08-13 | @ BOS | 115 | L 4-16 | 68-47 | 1 | 33,601 | Jeff Robinson | Mike Boddicker | Mike Boddicker | Jeff Robinson | Tom Bolton | 519 | 449 | 70 |
| 1988-08-14 | @ BOS | 116 | W 18-6 | 69-47 | 1 | 33,757 | Eric King | Roger Clemens | Eric King | Roger Clemens | | 537 | 455 | 82 |
| 1988-08-15 | vs MIN | 117 | L 1-2 | 69-48 | 1 | 32,700 | Walt Terrell | Frank Viola | Frank Viola | Walt Terrell | | 538 | 457 | 81 |
| 1988-08-16 | vs MIN | 118 | L 1-4 | 69-49 | 1 | 29,534 | Jack Morris | Bert Blyleven | Bert Blyleven | Jack Morris | Jeff Reardon | 539 | 461 | 78 |
| 1988-08-17 | vs MIN | 119 | L 1-2 | 69-50 | 1 | 34,622 | Doyle Alexander | Allan Anderson | Allan Anderson | Doyle Alexander | Jeff Reardon | 540 | 463 | 77 |
| 1988-08-18 | vs CHA | 120 | W 6-4 | 70-50 | 1 | 25,279 | Jeff Robinson | Melido Perez | Mike Henneman | Bobby Thigpen | | 546 | 467 | 79 |
| 1988-08-19 | vs CHA | 121 | W 5-4 | 71-50 | 1 | 37,313 | Frank Tanana | Bill Long | Frank Tanana | Bill Long | Guillermo Hernandez | 551 | 471 | 80 |
| 1988-08-20 | vs CHA | 122 | W 2-1 | 72-50 | 1 | 43,419 | Walt Terrell | Jeff Bittiger | Walt Terrell | Jeff Bittiger | Guillermo Hernandez | 553 | 472 | 81 |
| 1988-08-21 | vs CHA | 123 | W 5-0 | 73-50 | 1 | 39,147 | Jack Morris | Jack McDowell | Jack Morris | Jack McDowell | | 558 | 472 | 86 |
| 1988-08-22 | @ MIN | 124 | L 0-7 | 73-51 | 1 | 37,704 | Doyle Alexander | Allan Anderson | Allan Anderson | Doyle Alexander | | 558 | 479 | 79 |
| 1988-08-23 | @ MIN | 125 | L 5-7 | 73-52 | 1 | 40,935 | Jeff Robinson | Charlie Lea | Jeff Reardon | Mike Henneman | | 563 | 486 | 77 |
| 1988-08-24 | @ MIN | 126 | L 2-8 | 73-53 | 1 | 46,054 | Frank Tanana | Freddie Toliver | Freddie Toliver | Frank Tanana | | 565 | 494 | 71 |
| 1988-08-26 | @ MIL | 127 | W 3-2 | 74-53 | 1 | 35,275 | Walt Terrell | Don August | Mike Henneman | Chris Bosio | Guillermo Hernandez | 568 | 496 | 72 |
| 1988-08-27 | @ MIL | 128 | L 5-6 | 74-54 | 1 | 50,907 | Jack Morris | Mike Birkbeck | Chuck Crim | Paul Gibson | | 573 | 502 | 71 |
| 1988-08-28 | @ MIL | 129 | L 10-12 | 74-55 | 1 | 37,818 | Doyle Alexander | Bill Wegman | Odell Jones | Mike Henneman | Chris Bosio | 583 | 514 | 69 |
| 1988-08-29 | @ CHA | 130 | L 2-3 | 74-56 | 1 | 14,916 | Steve Searcy | Bill Long | Bill Long | Steve Searcy | Bobby Thigpen | 585 | 517 | 68 |
| 1988-08-30 | @ CHA | 131 | L 1-4 | 74-57 | 1 | 11,485 | Walt Terrell | Jeff Bittiger | Jeff Bittiger | Walt Terrell | Barry Jones | 586 | 521 | 65 |
| 1988-08-31 | @ CHA | 132 | W 9-3 | 75-57 | 1 | 12,693 | Jack Morris | Jack McDowell | Jack Morris | John Davis | | 595 | 524 | 71 |
| 1988-09-01 | vs MIL | 133 | L 2-6 | 75-58 | 1 | 21,852 | Doyle Alexander | Mike Birkbeck | Mike Birkbeck | Doyle Alexander | Chris Bosio | 597 | 530 | 67 |
| 1988-09-02 | vs MIL | 134 | L 0-5 | 75-59 | 1 | 23,437 | Frank Tanana | Bill Wegman | Bill Wegman | Frank Tanana | | 597 | 535 | 62 |
| 1988-09-03 | vs MIL | 135 | L 3-7 | 75-60 | 1 | 26,661 | Steve Searcy | Tom Filer | Paul Mirabella | Steve Searcy | | 600 | 542 | 58 |
| 1988-09-04 | vs MIL | 136 | L 1-6 | 75-61 | 2 | 27,755 | Walt Terrell | Teddy Higuera | Teddy Higuera | Walt Terrell | | 601 | 548 | 53 |
| 1988-09-05 | vs TOR | 137 | L 4-5 | 75-62 | 2 | 21,913 | Jack Morris | Mike Flanagan | Todd Stottlemyre | Guillermo Hernandez | Duane Ward | 605 | 553 | 52 |
| 1988-09-06 | vs TOR | 138 | L 3-7 | 75-63 | 2 | 18,299 | Doyle Alexander | Jimmy Key | Jimmy Key | Doyle Alexander | Duane Ward | 608 | 560 | 48 |
| 1988-09-07 | vs TOR | 139 | W 4-3 | 76-63 | 2 | 21,614 | Frank Tanana | Dave Stieb | Mike Henneman | John Cerutti | | 612 | 563 | 49 |
| 1988-09-08 | @ NYA | 140 | L 4-7 | 76-64 | 2 | 27,589 | Ted Power | Ron Guidry | Hipolito Pena | Mike Henneman | | 616 | 570 | 46 |
| 1988-09-09 | @ NYA | 141 | L 2-3 | 76-65 | 2 | 35,335 | Walt Terrell | Richard Dotson | Dale Mohorcic | Walt Terrell | | 618 | 573 | 45 |
| 1988-09-10 | @ NYA | 142 | L 4-9 | 76-66 | 2 | 45,418 | Jack Morris | Rick Rhoden | Rick Rhoden | Jack Morris | | 622 | 582 | 40 |
| 1988-09-11 | @ NYA | 143 | L 4-5 | 76-67 | 3 | 39,008 | Doyle Alexander | Al Leiter | Steve Shields | Guillermo Hernandez | | 626 | 587 | 39 |
| 1988-09-12 | @ TOR | 144 | W 6-5 | 77-67 | 2 | 31,354 | Frank Tanana | Jimmy Key | Mark Huismann | Tom Henke | Guillermo Hernandez | 632 | 592 | 40 |
| 1988-09-13 | @ TOR | 145 | L 1-9 | 77-68 | 3 | 32,141 | Ted Power | Dave Stieb | Dave Stieb | Ted Power | | 633 | 601 | 32 |
| 1988-09-14 | @ TOR | 146 | L 2-3 | 77-69 | 3 | 32,469 | Walt Terrell | Jim Clancy | Duane Ward | Walt Terrell | | 635 | 604 | 31 |
| 1988-09-16 | vs BAL | 147 | W 8-7 | 78-69 | 3 | 21,001 | Jack Morris | Jeff Ballard | Guillermo Hernandez | Mark Thurmond | | 643 | 611 | 32 |
| 1988-09-17 | vs BAL | 148 | W 7-3 | 79-69 | 2 | 27,842 | Doyle Alexander | Mark Williamson | Doyle Alexander | Gregg Olson | Mike Henneman | 650 | 614 | 36 |
| 1988-09-18 | vs BAL | 149 | L 0-2 | 79-70 | 2 | 29,728 | Frank Tanana | Bob Milacki | Bob Milacki | Frank Tanana | Tom Niedenfuer | 650 | 616 | 34 |
| 1988-09-19 | vs CLE | 150 | L 3-4 | 79-71 | 4 | 15,383 | Walt Terrell | Rich Yett | Don Gordon | Mike Henneman | Doug Jones | 653 | 620 | 33 |
| 1988-09-20 | vs CLE | 151 | W 3-1 | 80-71 | 4 | 14,593 | Jack Morris | John Farrell | Jack Morris | Scott Bailes | | 656 | 621 | 35 |
| 1988-09-21 | vs CLE | 152 | W 3-2 | 81-71 | 4 | 14,707 | Doyle Alexander | Tom Candiotti | Doyle Alexander | Brad Havens | Eric King | 659 | 623 | 36 |
| 1988-09-22 | @ BAL | 153 | W 7-4 | 82-71 | 4 | 17,164 | Frank Tanana | Dave J. Schmidt | Ted Power | Dave J. Schmidt | Mike Henneman | 666 | 627 | 39 |
| 1988-09-23 | @ BAL | 154 | L 4-5 | 82-72 | 4 | 24,792 | Walt Terrell | Bob Milacki | Tom Niedenfuer | Walt Terrell | | 670 | 632 | 38 |
| 1988-09-25 | @ BAL | 155 | W 2-1 | 84-72 | 2 | 0 | Jack Morris | Mark Williamson | Jack Morris | Mark Williamson | | 672 | 633 | 39 |
| 1988-09-25 | @ BAL | 156 | W 7-4 | 84-72 | 2 | 21,754 | Doyle Alexander | Jose Bautista | Doyle Alexander | Tom Niedenfuer | Guillermo Hernandez | 679 | 637 | 42 |
| 1988-09-26 | @ CLE | 157 | W 6-3 | 85-72 | 2 | 4,709 | Eric King | John Farrell | Eric King | John Farrell | Mike Henneman | 685 | 640 | 45 |
| 1988-09-27 | @ CLE | 158 | L 0-4 | 85-73 | 3 | 4,626 | Frank Tanana | Tom Candiotti | Tom Candiotti | Frank Tanana | | 685 | 644 | 41 |
| 1988-09-28 | @ CLE | 159 | L 2-4 | 85-74 | 4 | 5,262 | Walt Terrell | Greg Swindell | Greg Swindell | Walt Terrell | Doug Jones | 687 | 648 | 39 |
| 1988-09-30 | vs NYA | 160 | W 6-2 | 86-74 | 2 | 34,176 | Jack Morris | Rick Rhoden | Jack Morris | Rick Rhoden | | 693 | 650 | 43 |
| 1988-10-01 | vs NYA | 161 | W 6-5 | 87-74 | 2 | 39,960 | Doyle Alexander | Tommy John | Mike Henneman | Neil Allen | | 699 | 655 | 44 |
| 1988-10-02 | vs NYA | 162 | W 4-3 | 88-74 | 2 | 35,359 | Frank Tanana | Pat Clements | Paul Gibson | Dave Righetti | | 703 | 658 | 45 |