| 1983-04-05 | vs MIL | 1 | W 3-2 | 1-0 | 4 | 34,177 | Bruce Kison | Don Sutton | Bruce Kison | Don Sutton | Andy Hassler | 3 | 2 | 1 |
| 1983-04-06 | vs MIL | 2 | W 4-3 | 2-0 | 3 | 28,162 | Tommy John | Mike Caldwell | Tommy John | Mike Caldwell | | 7 | 5 | 2 |
| 1983-04-07 | vs MIL | 3 | L 3-5 | 2-1 | 3 | 30,145 | Mike Witt | Jerry Augustine | Jerry Augustine | Mike Witt | | 10 | 10 | 0 |
| 1983-04-08 | @ OAK | 4 | L 3-5 | 2-2 | 6 | 21,341 | Geoff Zahn | Chris Codiroli | Dave Beard | Geoff Zahn | | 13 | 15 | -2 |
| 1983-04-09 | @ OAK | 5 | W 10-2 | 3-2 | 4 | 22,507 | Ken Forsch | Matt Keough | Ken Forsch | Matt Keough | Luis Sanchez | 23 | 17 | 6 |
| 1983-04-10 | @ OAK | 6 | L 4-11 | 3-3 | 6 | 28,590 | Bruce Kison | Bill Krueger | Bill Krueger | Bruce Kison | | 27 | 28 | -1 |
| 1983-04-11 | vs SEA | 7 | W 6-1 | 4-3 | 3 | 22,588 | Tommy John | Matt Young | Tommy John | Matt Young | | 33 | 29 | 4 |
| 1983-04-12 | vs SEA | 8 | L 1-8 | 4-4 | 5 | 22,912 | Mike Witt | Bob Stoddard | Bob Stoddard | Mike Witt | | 34 | 37 | -3 |
| 1983-04-13 | vs SEA | 9 | W 6-1 | 5-4 | 4 | 24,002 | Geoff Zahn | Mike Moore | Geoff Zahn | Mike Moore | | 40 | 38 | 2 |
| 1983-04-15 | @ MIN | 10 | W 8-2 | 6-4 | 4 | 7,323 | Ken Forsch | Frank Viola | Ken Forsch | Frank Viola | | 48 | 40 | 8 |
| 1983-04-16 | @ MIN | 11 | W 9-5 | 7-4 | 2 | 9,974 | Bruce Kison | Bryan Oelkers | Bruce Kison | Bryan Oelkers | | 57 | 45 | 12 |
| 1983-04-17 | @ MIN | 12 | L 8-11 | 7-5 | 3 | 23,010 | Tommy John | Brad Havens | Len Whitehouse | Dave Goltz | Ron Davis | 65 | 56 | 9 |
| 1983-04-18 | vs OAK | 13 | L 3-5 | 7-6 | 4 | 27,780 | Mike Witt | Tom Underwood | Tom Underwood | Mike Witt | Steve Baker | 68 | 61 | 7 |
| 1983-04-21 | vs OAK | 14 | W 6-2 | 9-6 | 3 | 0 | Geoff Zahn | Chris Codiroli | Geoff Zahn | Chris Codiroli | | 74 | 63 | 11 |
| 1983-04-21 | vs OAK | 15 | W 6-5 | 9-6 | 3 | 29,400 | Ken Forsch | Matt Keough | Ken Forsch | Matt Keough | Luis Sanchez | 80 | 68 | 12 |
| 1983-04-22 | vs BAL | 16 | W 6-5 | 10-6 | 2 | 31,794 | Bruce Kison | Mike Flanagan | Luis Sanchez | Don Welchel | | 86 | 73 | 13 |
| 1983-04-23 | vs BAL | 17 | L 1-3 | 10-7 | 1 | 63,073 | Tommy John | Scott McGregor | Scott McGregor | Tommy John | | 87 | 76 | 11 |
| 1983-04-24 | vs BAL | 18 | W 7-3 | 11-7 | 2 | 43,521 | Dave Goltz | Dennis Martinez | Mike Witt | Dennis Martinez | | 94 | 79 | 15 |
| 1983-04-27 | vs DET | 19 | W 13-3 | 12-7 | 1 | 28,776 | Geoff Zahn | Milt Wilcox | Geoff Zahn | Milt Wilcox | Mike Witt | 107 | 82 | 25 |
| 1983-04-29 | vs BOS | 20 | L 5-6 | 12-8 | 2 | 43,308 | Bruce Kison | Bruce Hurst | Luis Aponte | Luis Sanchez | Bob Stanley | 112 | 88 | 24 |
| 1983-04-30 | vs BOS | 21 | W 4-1 | 13-8 | 1 | 39,507 | Tommy John | John Tudor | Doug Corbett | Mark Clear | | 116 | 89 | 27 |
| 1983-05-01 | vs BOS | 22 | L 9-10 | 13-9 | 2 | 37,645 | Dave Goltz | Mike Brown | Bob Stanley | Andy Hassler | | 125 | 99 | 26 |
| 1983-05-03 | @ BAL | 23 | L 2-4 | 13-10 | 3 | 20,837 | Geoff Zahn | Mike Flanagan | Mike Flanagan | Geoff Zahn | | 127 | 103 | 24 |
| 1983-05-04 | @ BAL | 24 | W 16-8 | 14-10 | 1 | 17,448 | Ken Forsch | Scott McGregor | Luis Sanchez | Scott McGregor | | 143 | 111 | 32 |
| 1983-05-06 | @ DET | 25 | W 4-2 | 15-10 | 1 | 18,616 | Bruce Kison | Milt Wilcox | Bruce Kison | Milt Wilcox | Mike Witt | 147 | 113 | 34 |
| 1983-05-07 | @ DET | 26 | W 6-5 | 16-10 | 1 | 15,003 | Geoff Zahn | Dan Petry | Luis Sanchez | Aurelio Lopez | | 153 | 118 | 35 |
| 1983-05-08 | @ DET | 27 | L 1-5 | 16-11 | 1 | 9,924 | Ken Forsch | Jack Morris | Jack Morris | Ken Forsch | | 154 | 123 | 31 |
| 1983-05-09 | @ BOS | 28 | L 2-8 | 16-12 | 1 | 16,148 | Tommy John | Bruce Hurst | Bob Stanley | Tommy John | | 156 | 131 | 25 |
| 1983-05-10 | @ BOS | 29 | W 6-5 | 17-12 | 1 | 15,775 | Bill Travers | Bob Ojeda | Luis Sanchez | Luis Aponte | Mike Witt | 162 | 136 | 26 |
| 1983-05-11 | @ BOS | 30 | W 3-1 | 18-12 | 1 | 16,978 | Bruce Kison | John Tudor | Bruce Kison | John Tudor | | 165 | 137 | 28 |
| 1983-05-13 | vs MIN | 31 | L 4-5 | 18-13 | 1 | 29,469 | Geoff Zahn | Frank Viola | Len Whitehouse | Mike Witt | Ron Davis | 169 | 142 | 27 |
| 1983-05-14 | vs MIN | 32 | L 1-2 | 18-14 | 1 | 44,047 | Ken Forsch | Bobby Castillo | Ken Schrom | Ken Forsch | Ron Davis | 170 | 144 | 26 |
| 1983-05-15 | vs MIN | 33 | L 6-8 | 18-15 | 1 | 30,840 | Tommy John | Jack O'Connor | Pete Filson | Dave Goltz | Ron Davis | 176 | 152 | 24 |
| 1983-05-17 | @ SEA | 34 | W 3-1 | 19-15 | 2 | 7,313 | Bruce Kison | Gaylord Perry | Bruce Kison | Gaylord Perry | | 179 | 153 | 26 |
| 1983-05-18 | @ SEA | 35 | L 1-2 | 19-16 | 2 | 6,299 | Geoff Zahn | Bob Stoddard | Bob Stoddard | Geoff Zahn | Bill Caudill | 180 | 155 | 25 |
| 1983-05-19 | @ SEA | 36 | L 0-1 | 19-17 | 3 | 6,585 | Ken Forsch | Matt Young | Matt Young | Ken Forsch | | 180 | 156 | 24 |
| 1983-05-20 | vs CLE | 37 | W 5-4 | 20-17 | 3 | 26,650 | Tommy John | Juan Eichelberger | Tommy John | Juan Eichelberger | Mike Witt | 185 | 160 | 25 |
| 1983-05-21 | vs CLE | 38 | L 3-9 | 20-18 | 3 | 35,177 | Bill Travers | Bert Blyleven | Bert Blyleven | Bill Travers | | 188 | 169 | 19 |
| 1983-05-22 | vs CLE | 39 | W 9-0 | 21-18 | 2 | 37,646 | Bruce Kison | Len Barker | Bruce Kison | Len Barker | | 197 | 169 | 28 |
| 1983-05-23 | vs NYA | 40 | W 3-0 | 22-18 | 1 | 35,712 | Geoff Zahn | Dave Righetti | Geoff Zahn | Dave Righetti | | 200 | 169 | 31 |
| 1983-05-24 | vs NYA | 41 | W 7-6 | 23-18 | 1 | 41,042 | Ken Forsch | Bob Shirley | Mike Witt | Rudy May | | 207 | 175 | 32 |
| 1983-05-25 | vs NYA | 42 | W 7-1 | 24-18 | 1 | 45,385 | Tommy John | Shane Rawley | Tommy John | Shane Rawley | | 214 | 176 | 38 |
| 1983-05-27 | @ CLE | 43 | W 5-4 | 25-18 | 1 | 24,776 | Bruce Kison | Bert Blyleven | Luis Sanchez | Dan Spillner | | 219 | 180 | 39 |
| 1983-05-28 | @ CLE | 44 | W 7-4 | 26-18 | 1 | 9,805 | Geoff Zahn | Len Barker | Geoff Zahn | Len Barker | | 226 | 184 | 42 |
| 1983-05-29 | @ CLE | 45 | W 6-4 | 27-18 | 1 | 11,746 | Ken Forsch | Rick Sutcliffe | Mike Witt | Dan Spillner | | 232 | 188 | 44 |
| 1983-05-30 | @ CLE | 46 | L 5-6 | 27-19 | 1 | 5,137 | Tommy John | Lary Sorensen | Neal Heaton | Luis Sanchez | | 237 | 194 | 43 |
| 1983-05-31 | @ NYA | 47 | L 3-5 | 27-20 | 1 | 20,219 | Bill Travers | Shane Rawley | Dale Murray | Mike Witt | | 240 | 199 | 41 |
| 1983-06-01 | @ NYA | 48 | L 0-3 | 27-21 | 1 | 28,427 | Dave Goltz | Ron Guidry | Ron Guidry | Dave Goltz | | 240 | 202 | 38 |
| 1983-06-02 | @ NYA | 49 | W 9-8 | 28-21 | 1 | 30,217 | Geoff Zahn | Dave Righetti | Luis Sanchez | Rudy May | John Curtis | 249 | 210 | 39 |
| 1983-06-03 | @ MIL | 50 | W 3-0 | 29-21 | 1 | 26,612 | Ken Forsch | Don Sutton | Ken Forsch | Don Sutton | | 252 | 210 | 42 |
| 1983-06-04 | @ MIL | 51 | W 8-3 | 30-21 | 1 | 51,703 | Tommy John | Jerry Augustine | Tommy John | Jerry Augustine | | 260 | 213 | 47 |
| 1983-06-05 | @ MIL | 52 | L 4-5 | 30-22 | 1 | 45,835 | Bill Travers | Moose Haas | Moose Haas | Andy Hassler | | 264 | 218 | 46 |
| 1983-06-06 | @ MIL | 53 | L 7-9 | 30-23 | 1 | 17,183 | Dave Goltz | Bob McClure | Bob McClure | Dave Goltz | Tom Tellmann | 271 | 227 | 44 |
| 1983-06-07 | vs CHA | 54 | L 11-12 | 30-24 | 1 | 33,556 | Mike Witt | Richard Dotson | Dick Tidrow | Andy Hassler | | 282 | 239 | 43 |
| 1983-06-08 | vs CHA | 55 | W 7-4 | 31-24 | 1 | 28,754 | Ken Forsch | Jerry Koosman | Ken Forsch | Jerry Koosman | | 289 | 243 | 46 |
| 1983-06-09 | vs CHA | 56 | W 3-2 | 32-24 | 1 | 28,296 | Tommy John | Britt Burns | Tommy John | Dennis Lamp | | 292 | 245 | 47 |
| 1983-06-10 | vs TOR | 57 | W 5-3 | 33-24 | 1 | 32,751 | Bill Travers | Luis Leal | Curt Brown | Luis Leal | | 297 | 248 | 49 |
| 1983-06-11 | vs TOR | 58 | L 2-3 | 33-25 | 1 | 45,393 | Dave Goltz | Jim Gott | Jim Gott | Dave Goltz | Randy Moffitt | 299 | 251 | 48 |
| 1983-06-12 | vs TOR | 59 | L 5-6 | 33-26 | 1 | 32,587 | Byron McLaughlin | Dave Stieb | Stan Clarke | Curt Brown | Dave Geisel | 304 | 257 | 47 |
| 1983-06-13 | @ CHA | 60 | W 7-4 | 34-26 | 1 | 27,160 | Ken Forsch | Britt Burns | Ken Forsch | Britt Burns | | 311 | 261 | 50 |
| 1983-06-15 | @ CHA | 61 | L 2-5 | 34-27 | 1 | 24,561 | Tommy John | LaMarr Hoyt | LaMarr Hoyt | Tommy John | Juan Agosto | 313 | 266 | 47 |
| 1983-06-17 | @ TOR | 62 | L 3-6 | 34-28 | 1 | 31,586 | Bill Travers | Dave Stieb | Dave Stieb | Bill Travers | | 316 | 272 | 44 |
| 1983-06-18 | @ TOR | 63 | W 7-6 | 35-28 | 1 | 40,150 | Ken Forsch | Jim Clancy | Luis Sanchez | Stan Clarke | | 323 | 278 | 45 |
| 1983-06-19 | @ TOR | 64 | L 1-6 | 35-29 | 1 | 36,098 | Dave Goltz | Luis Leal | Luis Leal | Dave Goltz | | 324 | 284 | 40 |
| 1983-06-20 | @ TEX | 65 | W 10-9 | 36-29 | 1 | 22,412 | Tommy John | Frank Tanana | John Curtis | Jon Matlack | | 334 | 293 | 41 |
| 1983-06-21 | @ TEX | 66 | L 2-3 | 36-30 | 1 | 24,333 | Byron McLaughlin | Danny Darwin | Danny Darwin | Byron McLaughlin | Dave J. Schmidt | 336 | 296 | 40 |
| 1983-06-22 | @ TEX | 67 | L 1-9 | 36-31 | 2 | 29,197 | Bill Travers | Rick Honeycutt | Rick Honeycutt | Bill Travers | | 337 | 305 | 32 |
| 1983-06-23 | @ KCA | 68 | W 7-2 | 37-31 | 1 | 38,823 | Ken Forsch | Buddy Black | Ken Forsch | Buddy Black | | 344 | 307 | 37 |
| 1983-06-24 | @ KCA | 69 | L 3-11 | 37-32 | 3 | 29,370 | Tommy John | Vida Blue | Mike Armstrong | Tommy John | | 347 | 318 | 29 |
| 1983-06-25 | @ KCA | 70 | W 9-2 | 38-32 | 2 | 40,125 | Mike Witt | Keith Creel | Mike Witt | Keith Creel | | 356 | 320 | 36 |
| 1983-06-27 | vs TEX | 71 | W 8-0 | 39-32 | 1 | 42,578 | Bruce Kison | Rick Honeycutt | Bruce Kison | Rick Honeycutt | | 364 | 320 | 44 |
| 1983-06-28 | vs TEX | 72 | L 1-3 | 39-33 | 2 | 30,028 | Ken Forsch | Charlie Hough | Charlie Hough | Ken Forsch | Dave J. Schmidt | 365 | 323 | 42 |
| 1983-06-29 | vs TEX | 73 | W 2-1 | 40-33 | 1 | 30,464 | Tommy John | Mike Smithson | Luis Sanchez | Mike Smithson | | 367 | 324 | 43 |
| 1983-06-30 | vs TEX | 74 | L 2-4 | 40-34 | 2 | 30,190 | Mike Witt | Frank Tanana | Dave J. Schmidt | Luis Sanchez | | 369 | 328 | 41 |
| 1983-07-01 | vs KCA | 75 | W 7-6 | 41-34 | 2 | 34,428 | Byron McLaughlin | Vida Blue | Byron McLaughlin | Vida Blue | Luis Sanchez | 376 | 334 | 42 |
| 1983-07-02 | vs KCA | 76 | L 3-5 | 41-35 | 2 | 39,382 | Bruce Kison | Larry Gura | Larry Gura | Bruce Kison | Dan Quisenberry | 379 | 339 | 40 |
| 1983-07-03 | vs KCA | 77 | W 5-2 | 42-35 | 2 | 36,405 | Ken Forsch | Buddy Black | Ken Forsch | Buddy Black | | 384 | 341 | 43 |
| 1983-07-04 | vs KCA | 78 | L 1-5 | 42-36 | 2 | 63,132 | Tommy John | Paul Splittorff | Paul Splittorff | Tommy John | | 385 | 346 | 39 |
| 1983-07-08 | @ BOS | 79 | W 9-3 | 43-36 | 2 | 33,878 | Bruce Kison | Dennis Eckersley | Bruce Kison | Dennis Eckersley | | 394 | 349 | 45 |
| 1983-07-09 | @ BOS | 80 | L 3-10 | 43-37 | 2 | 32,667 | Ken Forsch | John Tudor | John Tudor | Ken Forsch | | 397 | 359 | 38 |
| 1983-07-10 | @ BOS | 81 | W 5-3 | 44-37 | 1 | 32,142 | Tommy John | Bruce Hurst | Tommy John | Bruce Hurst | Luis Sanchez | 402 | 362 | 40 |
| 1983-07-11 | @ DET | 82 | L 6-12 | 44-38 | 2 | 26,092 | Geoff Zahn | Dave Rozema | Dave Rozema | Geoff Zahn | Doug Bair | 408 | 374 | 34 |
| 1983-07-12 | @ DET | 83 | L 4-5 | 44-39 | 2 | 25,222 | Byron McLaughlin | Milt Wilcox | Howard Bailey | Mike Witt | | 412 | 379 | 33 |
| 1983-07-13 | @ DET | 84 | L 1-7 | 44-40 | 3 | 30,733 | Bruce Kison | Dan Petry | Dan Petry | Bruce Kison | | 413 | 386 | 27 |
| 1983-07-14 | @ BAL | 85 | L 1-5 | 44-41 | 3 | 26,608 | Ken Forsch | Scott McGregor | Scott McGregor | Ken Forsch | | 414 | 391 | 23 |
| 1983-07-15 | @ BAL | 86 | L 4-10 | 44-42 | 3 | 34,249 | Tommy John | Mike Boddicker | Mike Boddicker | Tommy John | | 418 | 401 | 17 |
| 1983-07-16 | @ BAL | 87 | W 8-5 | 45-42 | 2 | 40,952 | Geoff Zahn | Dennis Martinez | Geoff Zahn | Dennis Martinez | Luis Sanchez | 426 | 406 | 20 |
| 1983-07-17 | @ BAL | 88 | L 1-11 | 45-43 | 3 | 41,684 | Byron McLaughlin | Allan Ramirez | Allan Ramirez | Byron McLaughlin | | 427 | 417 | 10 |
| 1983-07-18 | vs BOS | 89 | L 2-7 | 45-44 | 2 | 34,391 | Bruce Kison | Dennis Eckersley | Dennis Eckersley | Bruce Kison | Bob Stanley | 429 | 424 | 5 |
| 1983-07-19 | vs BOS | 90 | W 6-1 | 46-44 | 2 | 35,758 | Ken Forsch | John Tudor | Ken Forsch | John Tudor | | 435 | 425 | 10 |
| 1983-07-20 | vs BOS | 91 | L 4-6 | 46-45 | 3 | 39,966 | Tommy John | Bruce Hurst | Bob Stanley | Tommy John | | 439 | 431 | 8 |
| 1983-07-21 | vs DET | 92 | L 1-5 | 47-46 | 4 | 0 | Mike Witt | Howard Bailey | Howard Bailey | Mike Witt | Aurelio Lopez | 440 | 436 | 4 |
| 1983-07-21 | vs DET | 93 | W 3-2 | 47-46 | 4 | 34,544 | Geoff Zahn | Dave Rozema | Geoff Zahn | Dave Rozema | Andy Hassler | 443 | 438 | 5 |
| 1983-07-22 | vs DET | 94 | L 11-13 | 47-47 | 4 | 32,249 | Byron McLaughlin | Milt Wilcox | Milt Wilcox | Byron McLaughlin | Aurelio Lopez | 454 | 451 | 3 |
| 1983-07-23 | vs DET | 95 | L 2-7 | 47-48 | 4 | 50,011 | Bruce Kison | Dan Petry | Dan Petry | Bruce Kison | | 456 | 458 | -2 |
| 1983-07-24 | vs DET | 96 | L 3-4 | 47-49 | 4 | 30,958 | Ken Forsch | Jack Morris | Aurelio Lopez | Luis Sanchez | | 459 | 462 | -3 |
| 1983-07-25 | vs BAL | 97 | W 5-2 | 48-49 | 4 | 24,127 | Tommy John | Mike Boddicker | Tommy John | Mike Boddicker | Andy Hassler | 464 | 464 | 0 |
| 1983-07-26 | vs BAL | 98 | L 4-5 | 48-50 | 4 | 32,668 | Geoff Zahn | Paul Mirabella | Dennis Martinez | Geoff Zahn | | 468 | 469 | -1 |
| 1983-07-27 | vs BAL | 99 | L 4-10 | 48-51 | 4 | 31,088 | Mike Witt | Allan Ramirez | Allan Ramirez | Mike Witt | Sammy Stewart | 472 | 479 | -7 |
| 1983-07-29 | vs OAK | 100 | L 2-5 | 48-52 | 4 | 43,662 | Ken Forsch | Tim Conroy | Tim Conroy | Ken Forsch | Tom Underwood | 474 | 484 | -10 |
| 1983-07-30 | vs OAK | 101 | L 8-13 | 48-54 | 4 | 0 | Bruce Kison | Chris Codiroli | Tom Burgmeier | Luis Sanchez | | 482 | 497 | -15 |
| 1983-07-30 | vs OAK | 102 | L 1-2 | 48-54 | 4 | 41,306 | Tommy John | Steve McCatty | Dave Beard | Tommy John | | 483 | 499 | -16 |
| 1983-07-31 | vs OAK | 103 | W 4-0 | 49-54 | 4 | 27,051 | Geoff Zahn | Gorman Heimueller | Geoff Zahn | Gorman Heimueller | | 487 | 499 | -12 |
| 1983-08-01 | @ MIN | 104 | W 12-6 | 50-55 | 3 | 0 | Mike Witt | Brad Havens | Mike Witt | Brad Havens | | 499 | 505 | -6 |
| 1983-08-01 | @ MIN | 105 | L 0-7 | 50-55 | 3 | 18,368 | Steve Brown | Rick Lysander | Rick Lysander | Steve Brown | | 499 | 512 | -13 |
| 1983-08-02 | @ MIN | 106 | W 2-1 | 51-55 | 3 | 13,064 | Ken Forsch | Bobby Castillo | Bruce Kison | Bobby Castillo | | 501 | 513 | -12 |
| 1983-08-03 | @ MIN | 107 | W 7-5 | 52-55 | 3 | 10,711 | Tommy John | Frank Viola | Bruce Kison | Mike Walters | | 508 | 518 | -10 |
| 1983-08-04 | @ SEA | 108 | L 5-11 | 52-56 | 3 | 8,865 | Rick Steirer | Glenn Abbott | Bryan Clark | John Curtis | Ed Vande Berg | 513 | 529 | -16 |
| 1983-08-05 | @ SEA | 109 | L 1-3 | 52-57 | 3 | 7,313 | Geoff Zahn | Matt Young | Bob Stoddard | Geoff Zahn | Bill Caudill | 514 | 532 | -18 |
| 1983-08-06 | @ SEA | 110 | L 1-2 | 52-58 | 4 | 26,440 | Mike Witt | Mike Moore | Mike Moore | Mike Witt | Bill Caudill | 515 | 534 | -19 |
| 1983-08-07 | @ SEA | 111 | W 4-3 | 53-58 | 4 | 8,722 | Ken Forsch | Bryan Clark | Ken Forsch | Bryan Clark | Bruce Kison | 519 | 537 | -18 |
| 1983-08-08 | vs MIN | 112 | L 2-4 | 53-59 | 5 | 37,307 | Tommy John | Ken Schrom | Ken Schrom | Tommy John | | 521 | 541 | -20 |
| 1983-08-09 | vs MIN | 113 | W 8-2 | 54-59 | 5 | 25,443 | Rick Steirer | Rick Lysander | Rick Steirer | Rick Lysander | Bruce Kison | 529 | 543 | -14 |
| 1983-08-10 | vs MIN | 114 | L 1-4 | 54-60 | 5 | 27,510 | Geoff Zahn | Bobby Castillo | Bobby Castillo | Geoff Zahn | | 530 | 547 | -17 |
| 1983-08-12 | vs SEA | 115 | L 6-7 | 54-61 | 5 | 37,552 | Mike Witt | Mike Moore | Mike Stanton | Luis Sanchez | Bill Caudill | 536 | 554 | -18 |
| 1983-08-13 | vs SEA | 116 | W 10-5 | 55-61 | 5 | 29,702 | Ken Forsch | Bryan Clark | Ken Forsch | Bob Stoddard | John Curtis | 546 | 559 | -13 |
| 1983-08-14 | vs SEA | 117 | W 7-2 | 56-61 | 5 | 23,754 | Tommy John | Jim Beattie | Tommy John | Jim Beattie | | 553 | 561 | -8 |
| 1983-08-15 | @ OAK | 118 | L 0-5 | 56-62 | 5 | 31,619 | Geoff Zahn | Gorman Heimueller | Gorman Heimueller | Geoff Zahn | | 553 | 566 | -13 |
| 1983-08-16 | @ OAK | 119 | L 0-4 | 56-63 | 5 | 16,560 | Rick Steirer | Chris Codiroli | Chris Codiroli | Rick Steirer | Dave Beard | 553 | 570 | -17 |
| 1983-08-17 | @ OAK | 120 | W 6-5 | 57-63 | 5 | 13,520 | Mike Witt | Mike Warren | Mike Witt | Mike Warren | John Curtis | 559 | 575 | -16 |
| 1983-08-19 | @ NYA | 121 | L 6-11 | 57-64 | 5 | 43,181 | Ken Forsch | Ron Guidry | Ron Guidry | Ken Forsch | | 565 | 586 | -21 |
| 1983-08-20 | @ NYA | 122 | L 2-6 | 57-65 | 5 | 42,356 | Tommy John | Shane Rawley | Shane Rawley | Tommy John | | 567 | 592 | -25 |
| 1983-08-21 | @ NYA | 123 | L 1-2 | 57-66 | 5 | 50,896 | Geoff Zahn | Dave Righetti | Rich Gossage | Geoff Zahn | | 568 | 594 | -26 |
| 1983-08-22 | @ CLE | 124 | W 7-3 | 58-66 | 5 | 6,184 | Rick Steirer | Rick Sutcliffe | Bruce Kison | Dan Spillner | | 575 | 597 | -22 |
| 1983-08-23 | @ CLE | 125 | W 5-2 | 59-66 | 5 | 7,001 | Mike Witt | Len Barker | Mike Witt | Len Barker | Luis Sanchez | 580 | 599 | -19 |
| 1983-08-24 | @ MIL | 126 | L 0-1 | 59-67 | 5 | 35,536 | John Curtis | Don Sutton | Jim Slaton | Andy Hassler | | 580 | 600 | -20 |
| 1983-08-25 | @ MIL | 127 | L 0-7 | 59-68 | 4 | 32,951 | Tommy John | Tom Candiotti | Tom Candiotti | Tommy John | | 580 | 607 | -27 |
| 1983-08-26 | vs NYA | 128 | L 2-3 | 59-69 | 4 | 42,945 | Geoff Zahn | Dave Righetti | Dave Righetti | Geoff Zahn | Rich Gossage | 582 | 610 | -28 |
| 1983-08-27 | vs NYA | 129 | W 7-6 | 60-69 | 4 | 45,747 | Rick Steirer | Ray Fontenot | Steve Brown | Rich Gossage | | 589 | 616 | -27 |
| 1983-08-28 | vs NYA | 130 | L 3-7 | 60-70 | 4 | 38,469 | Ken Forsch | John Montefusco | John Montefusco | Ken Forsch | George Frazier | 592 | 623 | -31 |
| 1983-08-29 | vs CLE | 131 | L 4-6 | 60-71 | 4 | 22,134 | Mike Witt | Neal Heaton | Neal Heaton | Mike Witt | Bud Anderson | 596 | 629 | -33 |
| 1983-08-30 | vs CLE | 132 | W 10-6 | 61-71 | 4 | 22,187 | Tommy John | Rick Sutcliffe | Rick Steirer | Mike Jeffcoat | | 606 | 635 | -29 |
| 1983-08-31 | vs CLE | 133 | L 5-7 | 61-72 | 4 | 22,659 | Geoff Zahn | Bert Blyleven | Rick Sutcliffe | Luis Sanchez | Jamie Easterly | 611 | 642 | -31 |
| 1983-09-02 | vs MIL | 134 | W 6-5 | 62-72 | 4 | 25,094 | Ken Forsch | Chuck Porter | Rick Steirer | Rick Waits | Andy Hassler | 617 | 647 | -30 |
| 1983-09-03 | vs MIL | 135 | L 3-4 | 62-73 | 4 | 34,312 | Mike Witt | Mike Caldwell | Mike Caldwell | Mike Witt | Pete Ladd | 620 | 651 | -31 |
| 1983-09-04 | vs MIL | 136 | W 5-3 | 63-73 | 4 | 23,970 | Tommy John | Don Sutton | Tommy John | Don Sutton | Luis Sanchez | 625 | 654 | -29 |
| 1983-09-05 | @ TOR | 137 | L 0-7 | 63-74 | 5 | 24,741 | Geoff Zahn | Jim Gott | Jim Gott | Geoff Zahn | | 625 | 661 | -36 |
| 1983-09-06 | @ TOR | 138 | L 4-6 | 63-75 | 5 | 19,176 | John Curtis | Doyle Alexander | Doyle Alexander | John Curtis | Jim Acker | 629 | 667 | -38 |
| 1983-09-07 | @ TOR | 139 | W 9-6 | 64-75 | 5 | 22,639 | Ken Forsch | Luis Leal | Luis Sanchez | Dave Geisel | | 638 | 673 | -35 |
| 1983-09-08 | @ CHA | 140 | L 5-8 | 64-76 | 5 | 34,006 | Mike Witt | Richard Dotson | Richard Dotson | Mike Witt | | 643 | 681 | -38 |
| 1983-09-09 | @ CHA | 141 | L 0-11 | 64-77 | 5 | 36,650 | Tommy John | Britt Burns | Britt Burns | Tommy John | | 643 | 692 | -49 |
| 1983-09-10 | @ CHA | 142 | L 6-7 | 64-78 | 5 | 43,097 | Geoff Zahn | Floyd Bannister | Salome Barojas | Steve Brown | | 649 | 699 | -50 |
| 1983-09-11 | @ CHA | 143 | L 4-5 | 64-79 | 5 | 41,878 | Ken Forsch | LaMarr Hoyt | LaMarr Hoyt | Ken Forsch | | 653 | 704 | -51 |
| 1983-09-13 | vs KCA | 144 | L 3-4 | 64-80 | 5 | 23,959 | Luis Sanchez | Buddy Black | Buddy Black | Luis Sanchez | Dan Quisenberry | 656 | 708 | -52 |
| 1983-09-14 | vs KCA | 145 | L 0-1 | 64-81 | 5 | 23,284 | Tommy John | Paul Splittorff | Mike Armstrong | Rick Steirer | | 656 | 709 | -53 |
| 1983-09-16 | vs TEX | 146 | W 8-6 | 65-81 | 5 | 21,850 | Geoff Zahn | Danny Darwin | Luis Sanchez | John Butcher | | 664 | 715 | -51 |
| 1983-09-17 | vs TEX | 147 | L 2-5 | 65-82 | 5 | 34,608 | Ken Forsch | Dave Stewart | Dave Stewart | Ken Forsch | Dave Tobik | 666 | 720 | -54 |
| 1983-09-18 | vs TEX | 148 | L 6-7 | 65-83 | 5 | 22,556 | Mike Witt | Frank Tanana | Victor Cruz | Bob Lacey | | 672 | 727 | -55 |
| 1983-09-19 | @ KCA | 149 | L 4-8 | 65-85 | 6 | 0 | Steve Brown | Buddy Black | Mike Armstrong | Andy Hassler | | 676 | 735 | -59 |
| 1983-09-19 | @ KCA | 150 | L 6-7 | 65-85 | 6 | 24,576 | John Curtis | Danny Jackson | Mark Huismann | Byron McLaughlin | | 682 | 742 | -60 |
| 1983-09-20 | @ KCA | 151 | W 6-4 | 66-85 | 5 | 15,003 | Tommy John | Paul Splittorff | Tommy John | Paul Splittorff | Mike Witt | 688 | 746 | -58 |
| 1983-09-21 | @ KCA | 152 | W 3-0 | 67-85 | 5 | 14,874 | Geoff Zahn | Gaylord Perry | Geoff Zahn | Gaylord Perry | | 691 | 746 | -55 |
| 1983-09-22 | vs CHA | 153 | L 2-3 | 67-86 | 5 | 24,668 | Ken Forsch | Jerry Koosman | Jerry Koosman | Ken Forsch | Juan Agosto | 693 | 749 | -56 |
| 1983-09-23 | vs CHA | 154 | L 1-2 | 67-87 | 5 | 24,358 | Mike Witt | Richard Dotson | Richard Dotson | Mike Witt | | 694 | 751 | -57 |
| 1983-09-24 | vs CHA | 155 | L 0-2 | 67-88 | 5 | 23,388 | Steve Brown | Britt Burns | Britt Burns | Steve Brown | | 694 | 753 | -59 |
| 1983-09-25 | vs CHA | 156 | L 5-8 | 67-89 | 6 | 38,575 | Tommy John | LaMarr Hoyt | LaMarr Hoyt | Tommy John | Dennis Lamp | 699 | 761 | -62 |
| 1983-09-26 | vs TOR | 157 | L 2-3 | 67-90 | 6 | 19,713 | Geoff Zahn | Doyle Alexander | Doyle Alexander | Bob Lacey | Roy Lee Jackson | 701 | 764 | -63 |
| 1983-09-27 | vs TOR | 158 | W 7-1 | 68-90 | 5 | 20,559 | Byron McLaughlin | Luis Leal | Byron McLaughlin | Luis Leal | John Curtis | 708 | 765 | -57 |
| 1983-09-28 | vs TOR | 159 | L 3-5 | 68-91 | 6 | 20,592 | Mike Witt | Jim Clancy | Jim Clancy | Mike Witt | Roy Lee Jackson | 711 | 770 | -59 |
| 1983-09-30 | @ TEX | 160 | L 3-4 | 68-92 | 6 | 9,232 | Tommy John | Frank Tanana | Tom Henke | Doug Corbett | | 714 | 774 | -60 |
| 1983-10-01 | @ TEX | 161 | W 6-5 | 69-92 | 6 | 11,356 | Geoff Zahn | Charlie Hough | Bob Lacey | Odell Jones | John Curtis | 720 | 779 | -59 |
| 1983-10-02 | @ TEX | 162 | W 2-0 | 70-92 | 6 | 8,727 | Steve Brown | Al Lachowicz | Steve Brown | Al Lachowicz | | 722 | 779 | -57 |