| 1983-04-05 | @ CAL | 1 | L 2-3 | - | | 34,177 | Don Sutton | Bruce Kison | Bruce Kison | Don Sutton | Andy Hassler | 2 | 3 | -1 |
| 1983-04-06 | @ CAL | 2 | L 3-4 | - | | 28,162 | Mike Caldwell | Tommy John | Tommy John | Mike Caldwell | | 5 | 7 | -2 |
| 1983-04-07 | @ CAL | 3 | W 5-3 | - | | 30,145 | Jerry Augustine | Mike Witt | Jerry Augustine | Mike Witt | | 10 | 10 | 0 |
| 1983-04-09 | @ KCA | 4 | L 2-5 | - | | 17,078 | Bob McClure | Larry Gura | Larry Gura | Bob McClure | Dan Quisenberry | 12 | 15 | -3 |
| 1983-04-10 | @ KCA | 5 | W 9-5 | - | | 18,047 | Moose Haas | Vida Blue | Tom Tellmann | Mike Armstrong | | 21 | 20 | 1 |
| 1983-04-12 | @ TOR | 6 | W 6-5 | - | | 11,413 | Don Sutton | Luis Leal | Don Sutton | Mike Morgan | Jamie Easterly | 27 | 25 | 2 |
| 1983-04-13 | @ TOR | 7 | L 2-7 | - | | 10,809 | Mike Caldwell | Jim Clancy | Jim Clancy | Mike Caldwell | | 29 | 32 | -3 |
| 1983-04-14 | @ TOR | 8 | W 5-4 | - | | 10,127 | Jerry Augustine | Jim Gott | Jim Slaton | Joey McLaughlin | | 34 | 36 | -2 |
| 1983-04-15 | vs KCA | 9 | L 3-4 | - | | 54,049 | Bob McClure | Larry Gura | Larry Gura | Bob McClure | Dan Quisenberry | 37 | 40 | -3 |
| 1983-04-17 | vs KCA | 10 | W 6-3 | - | | 22,128 | Mike Caldwell | Steve Renko | Mike Caldwell | Steve Renko | Pete Ladd | 43 | 43 | 0 |
| 1983-04-18 | @ BOS | 11 | W 14-0 | - | | 31,644 | Don Sutton | Mike Brown | Don Sutton | Mike Brown | | 57 | 43 | 14 |
| 1983-04-20 | @ BOS | 12 | L 4-5 | - | | 17,302 | Moose Haas | Dennis Eckersley | Mark Clear | Pete Ladd | | 61 | 48 | 13 |
| 1983-04-22 | @ TEX | 13 | L 2-3 | - | | 14,008 | Bob McClure | Danny Darwin | Danny Darwin | Bob McClure | | 63 | 51 | 12 |
| 1983-04-23 | @ TEX | 14 | W 3-0 | - | | 20,142 | Mike Caldwell | Rick Honeycutt | Mike Caldwell | Rick Honeycutt | | 66 | 51 | 15 |
| 1983-04-24 | @ TEX | 15 | W 3-1 | - | | 19,133 | Don Sutton | Charlie Hough | Don Sutton | Charlie Hough | Pete Ladd | 69 | 52 | 17 |
| 1983-04-26 | vs CHA | 16 | W 4-3 | - | | 19,558 | Moose Haas | LaMarr Hoyt | Jim Slaton | Kevin Hickey | | 73 | 55 | 18 |
| 1983-04-27 | vs CHA | 17 | W 6-2 | - | | 16,375 | Jerry Augustine | Floyd Bannister | Tom Tellmann | Floyd Bannister | Bob Gibson | 79 | 57 | 22 |
| 1983-04-29 | @ MIN | 18 | L 4-7 | - | | 18,896 | Bob McClure | Brad Havens | Brad Havens | Bob McClure | Albert Williams | 83 | 64 | 19 |
| 1983-04-30 | @ MIN | 19 | L 7-9 | - | | 23,267 | Mike Caldwell | Jack O'Connor | Ron Davis | Pete Ladd | | 90 | 73 | 17 |
| 1983-05-01 | @ MIN | 20 | W 8-4 | - | | 24,703 | Don Sutton | Frank Viola | Don Sutton | Albert Williams | | 98 | 77 | 21 |
| 1983-05-02 | @ CHA | 21 | W 8-4 | - | | 12,568 | Moose Haas | LaMarr Hoyt | Jim Slaton | LaMarr Hoyt | | 106 | 81 | 25 |
| 1983-05-03 | @ CHA | 22 | L 6-7 | - | | 13,113 | Chuck Porter | Richard Dotson | Richard Dotson | Chuck Porter | Kevin Hickey | 112 | 88 | 24 |
| 1983-05-04 | @ CHA | 23 | L 2-3 | - | | 17,097 | Bob McClure | Dennis Lamp | Dennis Lamp | Bob McClure | Kevin Hickey | 114 | 91 | 23 |
| 1983-05-06 | vs TEX | 24 | L 4-9 | - | | 18,042 | Mike Caldwell | Charlie Hough | John Butcher | Mike Caldwell | Odell Jones | 118 | 100 | 18 |
| 1983-05-08 | vs TEX | 25 | W 6-3 | - | | 14,763 | Don Sutton | Mike Smithson | Jim Slaton | Odell Jones | | 124 | 103 | 21 |
| 1983-05-10 | vs MIN | 26 | W 4-1 | - | | 10,195 | Moose Haas | Brad Havens | Moose Haas | Brad Havens | Tom Tellmann | 128 | 104 | 24 |
| 1983-05-11 | vs MIN | 27 | W 4-1 | - | | 14,549 | Bob McClure | Albert Williams | Bob McClure | Albert Williams | | 132 | 105 | 27 |
| 1983-05-12 | vs BOS | 28 | L 3-5 | - | | 12,369 | Mike Caldwell | Mike Brown | Mike Brown | Mike Caldwell | Bob Stanley | 135 | 110 | 25 |
| 1983-05-14 | vs BOS | 29 | W 8-7 | - | | 26,180 | Chuck Porter | Bruce Hurst | Bob Gibson | Mark Clear | | 143 | 117 | 26 |
| 1983-05-15 | vs BOS | 30 | L 1-6 | - | | 46,055 | Moose Haas | Bob Ojeda | Bob Ojeda | Moose Haas | Luis Aponte | 144 | 123 | 21 |
| 1983-05-16 | vs TOR | 31 | L 1-2 | - | | 8,298 | Bob McClure | Dave Stieb | Dave Stieb | Bob McClure | Randy Moffitt | 145 | 125 | 20 |
| 1983-05-17 | vs TOR | 32 | W 9-6 | - | | 9,304 | Mike Caldwell | Jim Clancy | Mike Caldwell | Jim Clancy | Tom Tellmann | 154 | 131 | 23 |
| 1983-05-18 | vs TOR | 33 | W 7-6 | - | | 16,485 | Don Sutton | Luis Leal | Jim Slaton | Dave Geisel | | 161 | 137 | 24 |
| 1983-05-20 | @ SEA | 34 | W 4-3 | - | | 7,536 | Moose Haas | Jim Beattie | Tom Tellmann | Bryan Clark | | 165 | 140 | 25 |
| 1983-05-21 | @ SEA | 35 | L 4-5 | - | | 21,280 | Bob McClure | Gene Nelson | Bryan Clark | Bob McClure | | 169 | 145 | 24 |
| 1983-05-22 | @ SEA | 36 | W 6-0 | - | | 37,807 | Mike Caldwell | Gaylord Perry | Mike Caldwell | Gaylord Perry | | 175 | 145 | 30 |
| 1983-05-23 | @ OAK | 37 | L 4-5 | - | | 24,029 | Don Sutton | Bill Krueger | Steve Baker | Jim Slaton | | 179 | 150 | 29 |
| 1983-05-24 | @ OAK | 38 | L 7-8 | - | | 12,198 | Jerry Augustine | Tim Conroy | Matt Keough | Jamie Easterly | Steve Baker | 186 | 158 | 28 |
| 1983-05-25 | @ OAK | 39 | W 7-6 | - | | 18,375 | Moose Haas | Tom Underwood | Moose Haas | Tom Underwood | Tom Tellmann | 193 | 164 | 29 |
| 1983-05-27 | vs SEA | 40 | L 5-7 | - | | 14,762 | Bob McClure | Gaylord Perry | Gaylord Perry | Tom Tellmann | Bill Caudill | 198 | 171 | 27 |
| 1983-05-28 | vs SEA | 41 | L 3-4 | - | | 28,880 | Mike Caldwell | Bob Stoddard | Ed Vande Berg | Jim Slaton | | 201 | 175 | 26 |
| 1983-05-29 | vs SEA | 42 | L 4-6 | - | | 25,301 | Don Sutton | Matt Young | Matt Young | Don Sutton | Bill Caudill | 205 | 181 | 24 |
| 1983-05-30 | vs SEA | 43 | W 6-3 | - | | 18,673 | Jerry Augustine | Jim Beattie | Jerry Augustine | Jim Beattie | Tom Tellmann | 211 | 184 | 27 |
| 1983-05-31 | vs OAK | 44 | W 5-2 | - | | 8,525 | Moose Haas | Tim Conroy | Moose Haas | Tim Conroy | | 216 | 186 | 30 |
| 1983-06-01 | vs OAK | 45 | L 5-7 | - | | 12,513 | Bob McClure | Mike Norris | Tom Burgmeier | Chuck Porter | Tom Underwood | 221 | 193 | 28 |
| 1983-06-02 | vs OAK | 46 | W 6-1 | - | | 16,722 | Mike Caldwell | Chris Codiroli | Mike Caldwell | Chris Codiroli | | 227 | 194 | 33 |
| 1983-06-03 | vs CAL | 47 | L 0-3 | - | | 26,612 | Don Sutton | Ken Forsch | Ken Forsch | Don Sutton | | 227 | 197 | 30 |
| 1983-06-04 | vs CAL | 48 | L 3-8 | - | | 51,703 | Jerry Augustine | Tommy John | Tommy John | Jerry Augustine | | 230 | 205 | 25 |
| 1983-06-05 | vs CAL | 49 | W 5-4 | - | | 45,835 | Moose Haas | Bill Travers | Moose Haas | Andy Hassler | | 235 | 209 | 26 |
| 1983-06-06 | vs CAL | 50 | W 9-7 | - | | 17,183 | Bob McClure | Dave Goltz | Bob McClure | Dave Goltz | Tom Tellmann | 244 | 216 | 28 |
| 1983-06-07 | @ BAL | 51 | L 4-6 | - | | 18,476 | Mike Caldwell | Dennis Martinez | Dennis Martinez | Mike Caldwell | Tippy Martinez | 248 | 222 | 26 |
| 1983-06-08 | @ BAL | 52 | L 3-7 | - | | 22,341 | Don Sutton | Allan Ramirez | Tim Stoddard | Tom Tellmann | | 251 | 229 | 22 |
| 1983-06-09 | @ BAL | 53 | L 7-10 | - | | 23,399 | Jerry Augustine | Mike Boddicker | Mike Boddicker | Jerry Augustine | Tippy Martinez | 258 | 239 | 19 |
| 1983-06-10 | vs NYA | 54 | L 1-7 | - | | 39,025 | Moose Haas | Shane Rawley | Shane Rawley | Moose Haas | | 259 | 246 | 13 |
| 1983-06-11 | vs NYA | 55 | W 6-2 | - | | 23,926 | Bob McClure | Ron Guidry | Bob McClure | Ron Guidry | Bob Gibson | 265 | 248 | 17 |
| 1983-06-12 | vs NYA | 56 | W 6-5 | - | | 45,364 | Mike Caldwell | Dave Righetti | Tom Tellmann | Rudy May | | 271 | 253 | 18 |
| 1983-06-13 | vs BAL | 57 | L 2-3 | - | | 21,532 | Don Sutton | Allan Ramirez | Allan Ramirez | Don Sutton | Tippy Martinez | 273 | 256 | 17 |
| 1983-06-15 | vs BAL | 58 | L 8-11 | - | | 38,368 | Rick Waits | Storm Davis | Tippy Martinez | Bob Gibson | | 281 | 267 | 14 |
| 1983-06-16 | vs BAL | 59 | W 2-1 | - | | 22,728 | Moose Haas | Scott McGregor | Jim Slaton | Tim Stoddard | | 283 | 268 | 15 |
| 1983-06-17 | @ NYA | 60 | L 2-7 | - | | 35,288 | Mike Caldwell | Dave Righetti | Dave Righetti | Mike Caldwell | | 285 | 275 | 10 |
| 1983-06-18 | @ NYA | 61 | L 4-5 | - | | 31,207 | Don Sutton | Jay Howell | George Frazier | Bob Gibson | | 289 | 280 | 9 |
| 1983-06-19 | @ NYA | 62 | L 3-8 | - | | 40,630 | Rick Waits | Matt Keough | Matt Keough | Rick Waits | George Frazier | 292 | 288 | 4 |
| 1983-06-20 | @ DET | 63 | L 1-4 | - | | 2,232 | Chuck Porter | Dave Rozema | Dave Rozema | Chuck Porter | Aurelio Lopez | 293 | 292 | 1 |
| 1983-06-21 | @ DET | 64 | W 10-3 | - | | 2,507 | Moose Haas | Juan Berenguer | Moose Haas | Juan Berenguer | | 303 | 295 | 8 |
| 1983-06-22 | @ DET | 65 | L 2-6 | - | | 26,221 | Mike Caldwell | Jack Morris | Jack Morris | Mike Caldwell | | 305 | 301 | 4 |
| 1983-06-24 | vs CLE | 66 | W 6-2 | - | | 46,037 | Don Sutton | Lary Sorensen | Don Sutton | Lary Sorensen | | 311 | 303 | 8 |
| 1983-06-25 | vs CLE | 67 | W 7-2 | - | | 53,852 | Bob McClure | Juan Eichelberger | Jim Slaton | Juan Eichelberger | | 318 | 305 | 13 |
| 1983-06-26 | vs CLE | 68 | W 4-3 | - | | 34,456 | Mike Caldwell | Bert Blyleven | Tom Tellmann | Bert Blyleven | Pete Ladd | 322 | 308 | 14 |
| 1983-06-28 | vs DET | 69 | L 4-5 | - | | 22,793 | Chuck Porter | Dan Petry | Aurelio Lopez | Jim Slaton | | 326 | 313 | 13 |
| 1983-06-29 | vs DET | 70 | W 4-3 | - | | 18,934 | Don Sutton | Juan Berenguer | Pete Ladd | Aurelio Lopez | | 330 | 316 | 14 |
| 1983-06-30 | vs DET | 71 | W 4-1 | - | | 36,494 | Bob McClure | Jack Morris | Bob McClure | Jack Morris | Tom Tellmann | 334 | 317 | 17 |
| 1983-07-01 | @ CLE | 72 | W 11-10 | - | | 14,784 | Mike Caldwell | Juan Eichelberger | Mike Caldwell | Juan Eichelberger | Jim Slaton | 345 | 327 | 18 |
| 1983-07-02 | @ CLE | 73 | W 6-5 | - | | 14,467 | Moose Haas | Bert Blyleven | Moose Haas | Bert Blyleven | Pete Ladd | 351 | 332 | 19 |
| 1983-07-03 | @ CLE | 74 | L 2-5 | - | | 50,008 | Chuck Porter | Rick Sutcliffe | Rick Sutcliffe | Chuck Porter | Bud Anderson | 353 | 337 | 16 |
| 1983-07-04 | @ CLE | 75 | W 8-3 | - | | 5,557 | Don Sutton | Len Barker | Don Sutton | Len Barker | | 361 | 340 | 21 |
| 1983-07-08 | @ CHA | 76 | W 4-3 | - | | 36,415 | Bob McClure | LaMarr Hoyt | Bob McClure | LaMarr Hoyt | Jerry Augustine | 365 | 343 | 22 |
| 1983-07-09 | @ CHA | 77 | L 3-8 | - | | 27,770 | Don Sutton | Jerry Koosman | Jerry Koosman | Don Sutton | Dick Tidrow | 368 | 351 | 17 |
| 1983-07-10 | @ CHA | 78 | W 12-9 | - | | 28,988 | Mike Caldwell | Richard Dotson | Jim Slaton | Salome Barojas | Pete Ladd | 380 | 360 | 20 |
| 1983-07-11 | @ TEX | 79 | L 4-5 | - | | 27,343 | Moose Haas | Mike Smithson | Dave Tobik | Jerry Augustine | | 384 | 365 | 19 |
| 1983-07-12 | @ TEX | 80 | W 9-2 | - | | 23,171 | Chuck Porter | Frank Tanana | Chuck Porter | Frank Tanana | | 393 | 367 | 26 |
| 1983-07-13 | @ TEX | 81 | W 6-2 | - | | 28,540 | Bob McClure | Danny Darwin | Bob McClure | Danny Darwin | Jim Slaton | 399 | 369 | 30 |
| 1983-07-14 | vs MIN | 82 | W 5-1 | - | | 20,316 | Don Sutton | Albert Williams | Don Sutton | Albert Williams | | 404 | 370 | 34 |
| 1983-07-15 | vs MIN | 83 | W 6-3 | - | | 28,343 | Mike Caldwell | Bobby Castillo | Mike Caldwell | Bobby Castillo | | 410 | 373 | 37 |
| 1983-07-16 | vs MIN | 84 | W 5-0 | - | | 46,519 | Moose Haas | Frank Viola | Moose Haas | Frank Viola | | 415 | 373 | 42 |
| 1983-07-17 | vs MIN | 85 | W 10-6 | - | | 41,021 | Chuck Porter | Ken Schrom | Chuck Porter | Ken Schrom | Jim Slaton | 425 | 379 | 46 |
| 1983-07-18 | vs TEX | 86 | W 4-3 | - | | 0 | Bob Gibson | Danny Darwin | Jerry Augustine | Danny Darwin | Pete Ladd | 429 | 382 | 47 |
| 1983-07-18 | vs TEX | 87 | W 5-4 | - | | 28,076 | Bob McClure | Charlie Hough | Tom Tellmann | Charlie Hough | Pete Ladd | 434 | 386 | 48 |
| 1983-07-19 | vs TEX | 88 | L 1-3 | - | | 21,236 | Don Sutton | Rick Honeycutt | Rick Honeycutt | Don Sutton | John Butcher | 435 | 389 | 46 |
| 1983-07-20 | vs TEX | 89 | W 4-3 | - | | 35,645 | Mike Caldwell | Mike Smithson | Tom Tellmann | Mike Smithson | Pete Ladd | 439 | 392 | 47 |
| 1983-07-21 | vs CHA | 90 | W 7-6 | - | | 29,609 | Moose Haas | Britt Burns | Pete Ladd | Juan Agosto | Jim Slaton | 446 | 398 | 48 |
| 1983-07-22 | vs CHA | 91 | L 1-2 | - | | 44,167 | Chuck Porter | Floyd Bannister | Floyd Bannister | Chuck Porter | Dennis Lamp | 447 | 400 | 47 |
| 1983-07-23 | vs CHA | 92 | W 8-7 | - | | 52,795 | Bob McClure | LaMarr Hoyt | Bob McClure | LaMarr Hoyt | Pete Ladd | 455 | 407 | 48 |
| 1983-07-24 | vs CHA | 93 | W 8-7 | - | | 46,171 | Don Sutton | Jerry Koosman | Pete Ladd | Dick Tidrow | | 463 | 414 | 49 |
| 1983-07-25 | @ MIN | 94 | L 3-17 | - | | 24,527 | Mike Caldwell | Frank Viola | Frank Viola | Mike Caldwell | | 466 | 431 | 35 |
| 1983-07-26 | @ MIN | 95 | L 5-6 | - | | 25,732 | Moose Haas | Ken Schrom | Len Whitehouse | Tom Tellmann | | 471 | 437 | 34 |
| 1983-07-27 | @ MIN | 96 | W 13-9 | - | | 34,003 | Chuck Porter | Albert Williams | Jim Slaton | Brad Havens | | 484 | 446 | 38 |
| 1983-07-29 | @ BOS | 97 | W 11-5 | - | | 33,250 | Bob McClure | Dennis Eckersley | Bob McClure | Dennis Eckersley | Tom Tellmann | 495 | 451 | 44 |
| 1983-07-30 | @ BOS | 98 | L 5-10 | - | | 30,900 | Don Sutton | John Tudor | John Tudor | Don Sutton | | 500 | 461 | 39 |
| 1983-07-31 | @ BOS | 99 | W 7-5 | - | | 29,800 | Moose Haas | Bruce Hurst | Moose Haas | Bob Stanley | Pete Ladd | 507 | 466 | 41 |
| 1983-08-01 | @ BOS | 100 | W 6-2 | - | | 29,620 | Chuck Porter | Bob Ojeda | Chuck Porter | Bob Ojeda | Tom Tellmann | 513 | 468 | 45 |
| 1983-08-02 | vs KCA | 101 | W 5-1 | - | | 0 | Bob Gibson | Gaylord Perry | Bob Gibson | Gaylord Perry | | 518 | 469 | 49 |
| 1983-08-02 | vs KCA | 102 | W 3-2 | - | | 40,808 | Mike Caldwell | Larry Gura | Mike Caldwell | Larry Gura | | 521 | 471 | 50 |
| 1983-08-03 | vs KCA | 103 | L 5-8 | - | | 25,182 | Bob McClure | Keith Creel | Keith Creel | Bob McClure | Dan Quisenberry | 526 | 479 | 47 |
| 1983-08-04 | vs KCA | 104 | L 2-6 | - | | 37,191 | Don Sutton | Buddy Black | Buddy Black | Don Sutton | | 528 | 485 | 43 |
| 1983-08-05 | vs TOR | 105 | W 7-0 | - | | 29,559 | Moose Haas | Jim Gott | Moose Haas | Jim Gott | | 535 | 485 | 50 |
| 1983-08-06 | vs TOR | 106 | W 3-0 | - | | 48,464 | Chuck Porter | Doyle Alexander | Chuck Porter | Doyle Alexander | | 538 | 485 | 53 |
| 1983-08-07 | vs TOR | 107 | W 9-6 | - | | 47,300 | Mike Caldwell | Luis Leal | Mike Caldwell | Luis Leal | Pete Ladd | 547 | 491 | 56 |
| 1983-08-08 | @ KCA | 108 | L 4-5 | - | | 0 | Bob Gibson | Larry Gura | Larry Gura | Jim Slaton | Dan Quisenberry | 551 | 496 | 55 |
| 1983-08-08 | @ KCA | 109 | W 8-5 | - | | 42,039 | Bob McClure | Steve Renko | Bob McClure | Steve Renko | Pete Ladd | 559 | 501 | 58 |
| 1983-08-09 | @ KCA | 110 | L 2-8 | - | | 26,635 | Don Sutton | Buddy Black | Buddy Black | Don Sutton | | 561 | 509 | 52 |
| 1983-08-10 | @ KCA | 111 | W 4-0 | - | | 25,211 | Moose Haas | Paul Splittorff | Moose Haas | Paul Splittorff | | 565 | 509 | 56 |
| 1983-08-11 | @ TOR | 112 | W 6-4 | - | | 27,620 | Chuck Porter | Doyle Alexander | Chuck Porter | Doyle Alexander | Pete Ladd | 571 | 513 | 58 |
| 1983-08-12 | @ TOR | 113 | L 4-5 | - | | 30,130 | Mike Caldwell | Luis Leal | Joey McLaughlin | Jim Slaton | | 575 | 518 | 57 |
| 1983-08-13 | @ TOR | 114 | L 1-3 | - | | 35,240 | Bob McClure | Jim Clancy | Jim Clancy | Bob McClure | Dave Geisel | 576 | 521 | 55 |
| 1983-08-14 | @ TOR | 115 | L 3-4 | - | | 42,240 | Bob Gibson | Dave Stieb | Dave Stieb | Pete Ladd | Joey McLaughlin | 579 | 525 | 54 |
| 1983-08-15 | vs BOS | 116 | W 2-0 | - | | 32,000 | Moose Haas | Bruce Hurst | Moose Haas | Bruce Hurst | Pete Ladd | 581 | 525 | 56 |
| 1983-08-16 | vs BOS | 117 | W 4-3 | - | | 40,269 | Chuck Porter | Doug Bird | Jim Slaton | Mark Clear | | 585 | 528 | 57 |
| 1983-08-17 | vs BOS | 118 | W 4-3 | - | | 0 | Mike Caldwell | Bob Ojeda | Tom Tellmann | Bob Ojeda | | 589 | 531 | 58 |
| 1983-08-17 | vs BOS | 119 | W 5-1 | - | | 34,038 | Tom Candiotti | John Henry Johnson | Tom Candiotti | John Henry Johnson | | 594 | 532 | 62 |
| 1983-08-19 | vs OAK | 120 | L 1-9 | - | | 43,898 | Don Sutton | Tim Conroy | Tim Conroy | Don Sutton | | 595 | 541 | 54 |
| 1983-08-20 | vs OAK | 121 | W 3-1 | - | | 51,722 | Bob McClure | Steve McCatty | Tom Tellmann | Steve McCatty | Pete Ladd | 598 | 542 | 56 |
| 1983-08-21 | vs OAK | 122 | W 7-1 | - | | 43,609 | Moose Haas | Chris Codiroli | Moose Haas | Chris Codiroli | Jim Slaton | 605 | 543 | 62 |
| 1983-08-22 | vs SEA | 123 | W 3-2 | - | | 22,244 | Chuck Porter | Matt Young | Chuck Porter | Bob Stoddard | | 608 | 545 | 63 |
| 1983-08-23 | vs SEA | 124 | L 0-5 | - | | 23,148 | Mike Caldwell | Mike Moore | Mike Moore | Mike Caldwell | | 608 | 550 | 58 |
| 1983-08-24 | vs CAL | 125 | W 1-0 | - | | 35,536 | Don Sutton | John Curtis | Jim Slaton | Andy Hassler | | 609 | 550 | 59 |
| 1983-08-25 | vs CAL | 126 | W 7-0 | - | | 32,951 | Tom Candiotti | Tommy John | Tom Candiotti | Tommy John | | 616 | 550 | 66 |
| 1983-08-26 | @ OAK | 127 | L 3-4 | - | | 20,027 | Moose Haas | Chris Codiroli | Chris Codiroli | Moose Haas | Dave Beard | 619 | 554 | 65 |
| 1983-08-27 | @ OAK | 128 | L 2-5 | - | | 26,110 | Chuck Porter | Gorman Heimueller | Gorman Heimueller | Chuck Porter | | 621 | 559 | 62 |
| 1983-08-28 | @ OAK | 129 | W 4-2 | - | | 24,052 | Mike Caldwell | Mike Warren | Mike Caldwell | Mike Warren | Jerry Augustine | 625 | 561 | 64 |
| 1983-08-29 | @ SEA | 130 | L 1-2 | - | | 6,120 | Don Sutton | Bryan Clark | Bryan Clark | Don Sutton | | 626 | 563 | 63 |
| 1983-08-30 | @ SEA | 131 | W 3-2 | - | | 15,218 | Tom Candiotti | Jim Beattie | Tom Candiotti | Jim Beattie | Pete Ladd | 629 | 565 | 64 |
| 1983-08-31 | @ SEA | 132 | L 1-4 | - | | 6,307 | Pete Vuckovich | Bob Stoddard | Bob Stoddard | Pete Vuckovich | Mike Stanton | 630 | 569 | 61 |
| 1983-09-02 | @ CAL | 133 | L 5-6 | - | | 25,094 | Chuck Porter | Ken Forsch | Rick Steirer | Rick Waits | Andy Hassler | 635 | 575 | 60 |
| 1983-09-03 | @ CAL | 134 | W 4-3 | - | | 34,312 | Mike Caldwell | Mike Witt | Mike Caldwell | Mike Witt | Pete Ladd | 639 | 578 | 61 |
| 1983-09-04 | @ CAL | 135 | L 3-5 | - | | 23,970 | Don Sutton | Tommy John | Tommy John | Don Sutton | Luis Sanchez | 642 | 583 | 59 |
| 1983-09-05 | vs NYA | 136 | W 3-1 | - | | 31,115 | Tom Candiotti | Shane Rawley | Tom Candiotti | Shane Rawley | Pete Ladd | 645 | 584 | 61 |
| 1983-09-06 | vs NYA | 137 | W 6-3 | - | | 19,540 | Pete Vuckovich | Dave Righetti | Jim Slaton | Dave Righetti | Pete Ladd | 651 | 587 | 64 |
| 1983-09-07 | vs NYA | 138 | L 5-11 | - | | 30,812 | Chuck Porter | Ray Fontenot | Ray Fontenot | Chuck Porter | Rich Gossage | 656 | 598 | 58 |
| 1983-09-08 | vs NYA | 139 | L 5-6 | - | | 30,682 | Mike Caldwell | Bob Shirley | Bob Shirley | Mike Caldwell | Rich Gossage | 661 | 604 | 57 |
| 1983-09-09 | vs DET | 140 | W 2-1 | - | | 0 | Moose Haas | Jack Morris | Moose Haas | Jack Morris | Pete Ladd | 663 | 605 | 58 |
| 1983-09-09 | vs DET | 141 | L 1-2 | - | | 2,137 | Don Sutton | Glenn Abbott | Glenn Abbott | Jim Slaton | Dave Rozema | 664 | 607 | 57 |
| 1983-09-10 | vs DET | 142 | L 0-4 | - | | 30,327 | Tom Candiotti | Juan Berenguer | Juan Berenguer | Tom Candiotti | | 664 | 611 | 53 |
| 1983-09-11 | vs DET | 143 | L 4-6 | - | | 10,970 | Pete Vuckovich | Dan Petry | Dan Petry | Pete Vuckovich | Aurelio Lopez | 668 | 617 | 51 |
| 1983-09-12 | @ NYA | 144 | L 0-1 | - | | 20,382 | Chuck Porter | Ray Fontenot | Ray Fontenot | Chuck Porter | Rich Gossage | 668 | 618 | 50 |
| 1983-09-13 | @ NYA | 145 | L 1-2 | - | | 18,482 | Mike Caldwell | Bob Shirley | Rich Gossage | Mike Caldwell | | 669 | 620 | 49 |
| 1983-09-14 | @ NYA | 146 | L 1-4 | - | | 24,319 | Don Sutton | Ron Guidry | Ron Guidry | Don Sutton | | 670 | 624 | 46 |
| 1983-09-16 | @ BAL | 147 | L 1-8 | - | | 34,899 | Tom Candiotti | Mike Boddicker | Mike Boddicker | Tom Candiotti | | 671 | 632 | 39 |
| 1983-09-17 | @ BAL | 148 | L 4-5 | - | | 41,137 | Bob Gibson | Mike Flanagan | Mike Flanagan | Bob Gibson | Tippy Martinez | 675 | 637 | 38 |
| 1983-09-18 | @ BAL | 149 | L 9-10 | - | | 35,804 | Jaime Cocanower | Jim Palmer | Tippy Martinez | Pete Ladd | | 684 | 647 | 37 |
| 1983-09-19 | @ BAL | 150 | L 7-8 | - | | 39,462 | Chuck Porter | Scott McGregor | Tim Stoddard | Tom Tellmann | | 691 | 655 | 36 |
| 1983-09-20 | @ CLE | 151 | W 11-7 | - | | 6,218 | Mike Caldwell | Rick Sutcliffe | Jim Slaton | Bud Anderson | Pete Ladd | 702 | 662 | 40 |
| 1983-09-21 | @ CLE | 152 | W 10-7 | - | | 4,135 | Don Sutton | Neal Heaton | Don Sutton | Neal Heaton | Pete Ladd | 712 | 669 | 43 |
| 1983-09-22 | @ CLE | 153 | L 5-9 | - | | 5,456 | Tom Candiotti | Lary Sorensen | Lary Sorensen | Tom Candiotti | | 717 | 678 | 39 |
| 1983-09-23 | vs BAL | 154 | L 2-4 | - | | 38,096 | Bob Gibson | Scott McGregor | Scott McGregor | Bob Gibson | Sammy Stewart | 719 | 682 | 37 |
| 1983-09-24 | vs BAL | 155 | W 5-2 | - | | 48,659 | Jaime Cocanower | Dennis Martinez | Jaime Cocanower | Dennis Martinez | Pete Ladd | 724 | 684 | 40 |
| 1983-09-25 | vs BAL | 156 | L 1-5 | - | | 45,181 | Chuck Porter | Storm Davis | Storm Davis | Chuck Porter | Tippy Martinez | 725 | 689 | 36 |
| 1983-09-27 | vs CLE | 157 | W 8-4 | - | | 11,514 | Mike Caldwell | Lary Sorensen | Mike Caldwell | Lary Sorensen | | 733 | 693 | 40 |
| 1983-09-28 | vs CLE | 158 | W 6-4 | - | | 11,976 | Don Sutton | Rick Behenna | Jim Slaton | Jamie Easterly | | 739 | 697 | 42 |
| 1983-09-29 | vs CLE | 159 | L 2-4 | - | | 15,331 | Tom Candiotti | Rick Sutcliffe | Rick Sutcliffe | Tom Candiotti | | 741 | 701 | 40 |
| 1983-09-30 | @ DET | 160 | W 6-2 | - | | 19,614 | Bob Gibson | Juan Berenguer | Bob Gibson | Juan Berenguer | Pete Ladd | 747 | 703 | 44 |
| 1983-10-01 | @ DET | 161 | W 10-1 | - | | 14,788 | Jaime Cocanower | Jack Morris | Jaime Cocanower | Jack Morris | | 757 | 704 | 53 |
| 1983-10-02 | @ DET | 162 | W 7-4 | - | | 18,815 | Chuck Porter | Dan Petry | Chuck Porter | Dan Petry | Pete Ladd | 764 | 708 | 56 |