| 1983-04-04 | @ OAK | 1 | W 8-5 | 1-0 | 1 | 34,831 | Rick Sutcliffe | Rick Langford | Rick Sutcliffe | Rick Langford | Dan Spillner | 8 | 5 | 3 |
| 1983-04-06 | @ OAK | 2 | L 3-5 | 1-1 | 4 | 19,121 | Bert Blyleven | Mike Norris | Mike Norris | Bert Blyleven | Dave Beard | 11 | 10 | 1 |
| 1983-04-07 | @ OAK | 3 | W 9-1 | 2-1 | 1 | 8,761 | Len Barker | Tom Underwood | Len Barker | Tom Underwood | | 20 | 11 | 9 |
| 1983-04-09 | vs BAL | 4 | W 8-4 | 3-1 | 1 | 52,150 | Rick Sutcliffe | Scott McGregor | Rick Sutcliffe | Sammy Stewart | Dan Spillner | 28 | 15 | 13 |
| 1983-04-10 | vs BAL | 5 | L 2-13 | 3-2 | 1 | 10,721 | Lary Sorensen | Dennis Martinez | Dennis Martinez | Lary Sorensen | | 30 | 28 | 2 |
| 1983-04-12 | vs TEX | 6 | L 1-2 | 3-3 | 2 | 5,133 | Bert Blyleven | Rick Honeycutt | Rick Honeycutt | Bert Blyleven | Odell Jones | 31 | 30 | 1 |
| 1983-04-13 | vs TEX | 7 | W 4-3 | 4-3 | 2 | 4,078 | Len Barker | Charlie Hough | Len Barker | Mike Mason | Dan Spillner | 35 | 33 | 2 |
| 1983-04-16 | @ BAL | 8 | L 0-2 | 5-4 | 1 | 0 | Lary Sorensen | Jim Palmer | Jim Palmer | Lary Sorensen | Tippy Martinez | 35 | 35 | 0 |
| 1983-04-16 | @ BAL | 9 | W 7-4 | 5-4 | 1 | 10,016 | Neal Heaton | Dennis Martinez | Neal Heaton | Dennis Martinez | Dan Spillner | 42 | 39 | 3 |
| 1983-04-17 | @ BAL | 10 | L 1-6 | 5-5 | 2 | 36,430 | Bert Blyleven | Mike Flanagan | Mike Flanagan | Bert Blyleven | | 43 | 45 | -2 |
| 1983-04-18 | @ BAL | 11 | L 1-4 | 5-6 | 3 | 9,610 | Len Barker | Scott McGregor | Scott McGregor | Len Barker | | 44 | 49 | -5 |
| 1983-04-19 | @ TOR | 12 | L 7-9 | 5-7 | 6 | 10,358 | Rick Sutcliffe | Jim Gott | Randy Moffitt | Dan Spillner | | 51 | 58 | -7 |
| 1983-04-20 | @ TOR | 13 | L 1-4 | 5-8 | 7 | 10,173 | Lary Sorensen | Dave Stieb | Dave Stieb | Lary Sorensen | | 52 | 62 | -10 |
| 1983-04-22 | vs CHA | 14 | W 5-1 | 6-8 | 6 | 5,393 | Bert Blyleven | Floyd Bannister | Bert Blyleven | Floyd Bannister | | 57 | 63 | -6 |
| 1983-04-23 | vs CHA | 15 | W 6-3 | 7-8 | 6 | 10,688 | Len Barker | Dennis Lamp | Len Barker | Dennis Lamp | | 63 | 66 | -3 |
| 1983-04-24 | vs CHA | 16 | L 3-9 | 7-9 | 7 | 6,274 | Rick Sutcliffe | Richard Dotson | Richard Dotson | Rick Sutcliffe | | 66 | 75 | -9 |
| 1983-04-26 | vs MIN | 17 | W 7-1 | 8-9 | 5 | 4,493 | Lary Sorensen | Bobby Castillo | Lary Sorensen | Bobby Castillo | | 73 | 76 | -3 |
| 1983-04-27 | vs MIN | 18 | L 3-5 | 8-10 | 7 | 6,824 | Bert Blyleven | Bryan Oelkers | Albert Williams | Ed Glynn | Rick Lysander | 76 | 81 | -5 |
| 1983-04-29 | @ KCA | 19 | L 5-6 | 8-11 | 7 | 15,787 | Len Barker | Vida Blue | Mike Armstrong | Dan Spillner | | 81 | 87 | -6 |
| 1983-04-30 | @ KCA | 20 | W 5-1 | 9-11 | 5 | 20,873 | Rick Sutcliffe | Steve Renko | Rick Sutcliffe | Steve Renko | Neal Heaton | 86 | 88 | -2 |
| 1983-05-01 | @ KCA | 21 | W 2-1 | 10-11 | 4 | 18,199 | Lary Sorensen | Larry Gura | Lary Sorensen | Larry Gura | Dan Spillner | 88 | 89 | -1 |
| 1983-05-03 | @ MIN | 22 | W 3-1 | 11-11 | 4 | 3,615 | Bert Blyleven | Bobby Castillo | Bert Blyleven | Bobby Castillo | Neal Heaton | 91 | 90 | 1 |
| 1983-05-04 | @ MIN | 23 | W 11-7 | 12-11 | 3 | 3,516 | Len Barker | Bryan Oelkers | Dan Spillner | Ron Davis | | 102 | 97 | 5 |
| 1983-05-05 | @ MIN | 24 | W 7-5 | 13-11 | 3 | 5,644 | Rick Sutcliffe | Brad Havens | Rick Sutcliffe | Brad Havens | Neal Heaton | 109 | 102 | 7 |
| 1983-05-06 | @ CHA | 25 | L 3-8 | 13-12 | 4 | 20,912 | Lary Sorensen | Floyd Bannister | Jerry Koosman | Lary Sorensen | | 112 | 110 | 2 |
| 1983-05-07 | @ CHA | 26 | L 3-4 | 13-13 | 4 | 18,245 | Juan Eichelberger | LaMarr Hoyt | LaMarr Hoyt | Juan Eichelberger | Kevin Hickey | 115 | 114 | 1 |
| 1983-05-08 | @ CHA | 27 | W 13-6 | 14-13 | 5 | 12,960 | Bert Blyleven | Richard Dotson | Bert Blyleven | Richard Dotson | | 128 | 120 | 8 |
| 1983-05-10 | vs KCA | 28 | W 4-1 | 15-13 | 5 | 6,195 | Len Barker | Vida Blue | Len Barker | Vida Blue | Neal Heaton | 132 | 121 | 11 |
| 1983-05-11 | vs KCA | 29 | W 2-0 | 16-13 | 5 | 7,748 | Rick Sutcliffe | Larry Gura | Rick Sutcliffe | Larry Gura | | 134 | 121 | 13 |
| 1983-05-12 | vs TOR | 30 | L 3-6 | 16-14 | 5 | 6,361 | Lary Sorensen | Jim Clancy | Jim Clancy | Lary Sorensen | Randy Moffitt | 137 | 127 | 10 |
| 1983-05-13 | vs TOR | 31 | W 5-1 | 17-14 | 4 | 10,900 | Juan Eichelberger | Mike Morgan | Juan Eichelberger | Mike Morgan | | 142 | 128 | 14 |
| 1983-05-14 | vs TOR | 32 | L 1-8 | 17-15 | 5 | 15,505 | Bert Blyleven | Luis Leal | Luis Leal | Bert Blyleven | Roy Lee Jackson | 143 | 136 | 7 |
| 1983-05-16 | @ TEX | 33 | L 1-3 | 17-16 | 5 | 18,481 | Len Barker | Rick Honeycutt | Rick Honeycutt | Len Barker | | 144 | 139 | 5 |
| 1983-05-17 | @ TEX | 34 | L 5-6 | 17-17 | 5 | 26,568 | Rick Sutcliffe | Jon Matlack | Dave J. Schmidt | Ed Glynn | | 149 | 145 | 4 |
| 1983-05-18 | @ TEX | 35 | L 2-3 | 17-18 | 6 | 13,203 | Lary Sorensen | Charlie Hough | Dave Tobik | Neal Heaton | | 151 | 148 | 3 |
| 1983-05-20 | @ CAL | 36 | L 4-5 | 17-19 | 6 | 26,650 | Juan Eichelberger | Tommy John | Tommy John | Juan Eichelberger | Mike Witt | 155 | 153 | 2 |
| 1983-05-21 | @ CAL | 37 | W 9-3 | 18-19 | 6 | 35,177 | Bert Blyleven | Bill Travers | Bert Blyleven | Bill Travers | | 164 | 156 | 8 |
| 1983-05-22 | @ CAL | 38 | L 0-9 | 18-20 | 6 | 37,646 | Len Barker | Bruce Kison | Bruce Kison | Len Barker | | 164 | 165 | -1 |
| 1983-05-23 | @ SEA | 39 | L 2-3 | 18-21 | 6 | 4,332 | Rick Sutcliffe | Bob Stoddard | Bob Stoddard | Rick Sutcliffe | Bill Caudill | 166 | 168 | -2 |
| 1983-05-24 | @ SEA | 40 | W 6-4 | 19-21 | 6 | 5,161 | Lary Sorensen | Matt Young | Neal Heaton | Bill Caudill | | 172 | 172 | 0 |
| 1983-05-25 | @ SEA | 41 | L 1-2 | 19-22 | 6 | 5,057 | Juan Eichelberger | Jim Beattie | Jim Beattie | Juan Eichelberger | Mike Stanton | 173 | 174 | -1 |
| 1983-05-27 | vs CAL | 42 | L 4-5 | 19-23 | 7 | 24,776 | Bert Blyleven | Bruce Kison | Luis Sanchez | Dan Spillner | | 177 | 179 | -2 |
| 1983-05-28 | vs CAL | 43 | L 4-7 | 19-24 | 7 | 9,805 | Len Barker | Geoff Zahn | Geoff Zahn | Len Barker | | 181 | 186 | -5 |
| 1983-05-29 | vs CAL | 44 | L 4-6 | 19-25 | 7 | 11,746 | Rick Sutcliffe | Ken Forsch | Mike Witt | Dan Spillner | | 185 | 192 | -7 |
| 1983-05-30 | vs CAL | 45 | W 6-5 | 20-25 | 7 | 5,137 | Lary Sorensen | Tommy John | Neal Heaton | Luis Sanchez | | 191 | 197 | -6 |
| 1983-05-31 | vs SEA | 46 | W 5-2 | 21-25 | 7 | 3,057 | Juan Eichelberger | Gene Nelson | Juan Eichelberger | Gene Nelson | Dan Spillner | 196 | 199 | -3 |
| 1983-06-01 | vs SEA | 47 | W 5-2 | 22-25 | 7 | 4,702 | Bert Blyleven | Gaylord Perry | Neal Heaton | Gaylord Perry | | 201 | 201 | 0 |
| 1983-06-02 | vs SEA | 48 | W 3-1 | 23-25 | 7 | 4,052 | Rick Sutcliffe | Bob Stoddard | Rick Sutcliffe | Bob Stoddard | | 204 | 202 | 2 |
| 1983-06-04 | vs OAK | 49 | L 3-6 | 23-26 | 7 | 9,014 | Lary Sorensen | Bill Krueger | Tom Burgmeier | Rick Waits | | 207 | 208 | -1 |
| 1983-06-05 | vs OAK | 50 | L 3-8 | 23-28 | 7 | 0 | Juan Eichelberger | Tom Underwood | Matt Keough | Neal Heaton | | 210 | 216 | -6 |
| 1983-06-05 | vs OAK | 51 | L 2-9 | 23-28 | 7 | 14,048 | Len Barker | Steve McCatty | Steve McCatty | Len Barker | | 212 | 225 | -13 |
| 1983-06-07 | @ NYA | 52 | W 2-1 | 24-28 | 7 | 18,972 | Bert Blyleven | Dave Righetti | Neal Heaton | Rich Gossage | | 214 | 226 | -12 |
| 1983-06-08 | @ NYA | 53 | L 5-6 | 24-29 | 7 | 16,278 | Rick Sutcliffe | Jay Howell | Rich Gossage | Dan Spillner | | 219 | 232 | -13 |
| 1983-06-10 | @ DET | 54 | L 1-7 | 24-30 | 7 | 31,119 | Lary Sorensen | Dave Rozema | Dave Rozema | Lary Sorensen | Aurelio Lopez | 220 | 239 | -19 |
| 1983-06-11 | @ DET | 55 | W 9-1 | 25-30 | 7 | 26,836 | Juan Eichelberger | Larry Pashnick | Juan Eichelberger | Larry Pashnick | | 229 | 240 | -11 |
| 1983-06-12 | @ DET | 56 | L 1-4 | 25-32 | 7 | 0 | Bert Blyleven | Milt Wilcox | Milt Wilcox | Bert Blyleven | | 230 | 244 | -14 |
| 1983-06-12 | @ DET | 57 | L 1-3 | 25-32 | 7 | 34,124 | Len Barker | Jack Morris | Jack Morris | Len Barker | | 231 | 247 | -16 |
| 1983-06-13 | vs NYA | 58 | W 9-0 | 26-32 | 7 | 13,517 | Rick Sutcliffe | Jay Howell | Rick Sutcliffe | Jay Howell | | 240 | 247 | -7 |
| 1983-06-14 | vs NYA | 59 | W 9-6 | 27-32 | 7 | 14,150 | Lary Sorensen | Bob Shirley | Lary Sorensen | Bob Shirley | Dan Spillner | 249 | 253 | -4 |
| 1983-06-15 | vs NYA | 60 | L 5-8 | 27-33 | 7 | 16,299 | Juan Eichelberger | Shane Rawley | Shane Rawley | Juan Eichelberger | | 254 | 261 | -7 |
| 1983-06-16 | vs NYA | 61 | L 1-8 | 27-34 | 7 | 19,016 | Bert Blyleven | Ron Guidry | Ron Guidry | Bert Blyleven | | 255 | 269 | -14 |
| 1983-06-17 | vs DET | 62 | L 4-11 | 27-35 | 7 | 11,465 | Len Barker | Jack Morris | Jack Morris | Len Barker | | 259 | 280 | -21 |
| 1983-06-18 | vs DET | 63 | W 12-8 | 28-35 | 7 | 14,625 | Rick Sutcliffe | Milt Wilcox | Rick Sutcliffe | Milt Wilcox | | 271 | 288 | -17 |
| 1983-06-19 | vs DET | 64 | W 7-2 | 29-35 | 7 | 19,900 | Lary Sorensen | Dan Petry | Lary Sorensen | Dan Petry | | 278 | 290 | -12 |
| 1983-06-20 | @ BOS | 65 | L 3-6 | 29-36 | 7 | 18,417 | Juan Eichelberger | Dennis Eckersley | Dennis Eckersley | Juan Eichelberger | Bob Stanley | 281 | 296 | -15 |
| 1983-06-21 | @ BOS | 66 | W 3-1 | 30-36 | 7 | 19,738 | Bert Blyleven | Bruce Hurst | Bert Blyleven | Bruce Hurst | | 284 | 297 | -13 |
| 1983-06-22 | @ BOS | 67 | W 9-4 | 31-36 | 6 | 19,755 | Len Barker | Bob Ojeda | Len Barker | Bob Ojeda | | 293 | 301 | -8 |
| 1983-06-23 | @ BOS | 68 | W 5-4 | 32-36 | 6 | 20,591 | Rick Sutcliffe | Doug Bird | Rick Sutcliffe | Doug Bird | Neal Heaton | 298 | 305 | -7 |
| 1983-06-24 | @ MIL | 69 | L 2-6 | 32-37 | 7 | 46,037 | Lary Sorensen | Don Sutton | Don Sutton | Lary Sorensen | | 300 | 311 | -11 |
| 1983-06-25 | @ MIL | 70 | L 2-7 | 32-38 | 7 | 53,852 | Juan Eichelberger | Bob McClure | Jim Slaton | Juan Eichelberger | | 302 | 318 | -16 |
| 1983-06-26 | @ MIL | 71 | L 3-4 | 32-39 | 7 | 34,456 | Bert Blyleven | Mike Caldwell | Tom Tellmann | Bert Blyleven | Pete Ladd | 305 | 322 | -17 |
| 1983-06-28 | vs BOS | 72 | L 3-11 | 32-40 | 7 | 5,355 | Rick Sutcliffe | Bob Ojeda | Mark Clear | Rick Sutcliffe | | 308 | 333 | -25 |
| 1983-06-29 | vs BOS | 73 | W 5-3 | 33-41 | 7 | 0 | Len Barker | John Tudor | Len Barker | Bob Stanley | Neal Heaton | 313 | 336 | -23 |
| 1983-06-29 | vs BOS | 74 | L 10-11 | 33-41 | 7 | 11,321 | Lary Sorensen | Mike Brown | John Henry Johnson | Bud Anderson | Doug Bird | 323 | 347 | -24 |
| 1983-07-01 | vs MIL | 75 | L 10-11 | 33-42 | 7 | 14,784 | Juan Eichelberger | Mike Caldwell | Mike Caldwell | Juan Eichelberger | Jim Slaton | 333 | 358 | -25 |
| 1983-07-02 | vs MIL | 76 | L 5-6 | 33-43 | 7 | 14,467 | Bert Blyleven | Moose Haas | Moose Haas | Bert Blyleven | Pete Ladd | 338 | 364 | -26 |
| 1983-07-03 | vs MIL | 77 | W 5-2 | 34-43 | 7 | 50,008 | Rick Sutcliffe | Chuck Porter | Rick Sutcliffe | Chuck Porter | Bud Anderson | 343 | 366 | -23 |
| 1983-07-04 | vs MIL | 78 | L 3-8 | 34-44 | 7 | 5,557 | Len Barker | Don Sutton | Don Sutton | Len Barker | | 346 | 374 | -28 |
| 1983-07-08 | @ MIN | 79 | W 10-4 | 35-44 | 7 | 11,529 | Bert Blyleven | Frank Viola | Bert Blyleven | Frank Viola | | 356 | 378 | -22 |
| 1983-07-09 | @ MIN | 80 | L 2-3 | 35-45 | 7 | 11,683 | Rick Sutcliffe | Ken Schrom | Ken Schrom | Rick Sutcliffe | Ron Davis | 358 | 381 | -23 |
| 1983-07-10 | @ MIN | 81 | L 4-6 | 35-46 | 7 | 7,287 | Juan Eichelberger | Albert Williams | Albert Williams | Juan Eichelberger | Ron Davis | 362 | 387 | -25 |
| 1983-07-11 | @ CHA | 82 | L 2-9 | 35-47 | 7 | 18,473 | Len Barker | Britt Burns | Britt Burns | Len Barker | | 364 | 396 | -32 |
| 1983-07-12 | @ CHA | 83 | L 0-8 | 35-48 | 7 | 16,799 | Lary Sorensen | Floyd Bannister | Floyd Bannister | Lary Sorensen | | 364 | 404 | -40 |
| 1983-07-13 | @ CHA | 84 | L 1-5 | 35-49 | 7 | 22,700 | Bert Blyleven | LaMarr Hoyt | LaMarr Hoyt | Bert Blyleven | | 365 | 409 | -44 |
| 1983-07-14 | vs KCA | 85 | W 4-3 | 36-49 | 7 | 11,013 | Rick Sutcliffe | Buddy Black | Rick Sutcliffe | Mike Armstrong | | 369 | 412 | -43 |
| 1983-07-15 | vs KCA | 86 | L 0-10 | 36-50 | 7 | 10,169 | Juan Eichelberger | Paul Splittorff | Paul Splittorff | Juan Eichelberger | | 369 | 422 | -53 |
| 1983-07-16 | vs KCA | 87 | W 17-3 | 37-50 | 7 | 10,086 | Len Barker | Gaylord Perry | Len Barker | Gaylord Perry | Neal Heaton | 386 | 425 | -39 |
| 1983-07-17 | vs KCA | 88 | L 2-7 | 37-51 | 7 | 20,907 | Lary Sorensen | Steve Renko | Don Hood | Dan Spillner | | 388 | 432 | -44 |
| 1983-07-18 | vs CHA | 89 | L 3-5 | 37-52 | 7 | 6,339 | Juan Eichelberger | LaMarr Hoyt | LaMarr Hoyt | Juan Eichelberger | Salome Barojas | 391 | 437 | -46 |
| 1983-07-19 | vs CHA | 90 | W 5-4 | 38-52 | 7 | 5,933 | Rick Sutcliffe | Jerry Koosman | Rick Sutcliffe | Dick Tidrow | | 396 | 441 | -45 |
| 1983-07-20 | vs CHA | 91 | L 2-8 | 38-53 | 7 | 6,296 | Neal Heaton | Richard Dotson | Richard Dotson | Neal Heaton | | 398 | 449 | -51 |
| 1983-07-22 | vs MIN | 92 | W 8-5 | 39-53 | 7 | 6,800 | Lary Sorensen | Ken Schrom | Jamie Easterly | Rick Lysander | Dan Spillner | 406 | 454 | -48 |
| 1983-07-23 | vs MIN | 93 | L 2-5 | 39-54 | 7 | 6,675 | Len Barker | Albert Williams | Albert Williams | Len Barker | Ron Davis | 408 | 459 | -51 |
| 1983-07-24 | vs MIN | 94 | L 5-7 | 39-56 | 7 | 0 | Rick Sutcliffe | Bobby Castillo | Bobby Castillo | Rick Sutcliffe | Ron Davis | 413 | 466 | -53 |
| 1983-07-24 | vs MIN | 95 | L 4-5 | 39-56 | 7 | 8,938 | Tom Brennan | Brad Havens | Brad Havens | Tom Brennan | Ron Davis | 417 | 471 | -54 |
| 1983-07-25 | @ KCA | 96 | L 1-6 | 39-57 | 7 | 37,652 | Neal Heaton | Paul Splittorff | Paul Splittorff | Neal Heaton | Dan Quisenberry | 418 | 477 | -59 |
| 1983-07-26 | @ KCA | 97 | W 2-0 | 40-57 | 7 | 25,243 | Lary Sorensen | Steve Renko | Lary Sorensen | Steve Renko | | 420 | 477 | -57 |
| 1983-07-27 | @ KCA | 98 | L 4-5 | 40-58 | 7 | 23,457 | Len Barker | Gaylord Perry | Gaylord Perry | Len Barker | Dan Quisenberry | 424 | 482 | -58 |
| 1983-07-29 | @ TOR | 99 | L 2-4 | 40-59 | 7 | 18,020 | Rick Sutcliffe | Jim Clancy | Jim Clancy | Rick Sutcliffe | | 426 | 486 | -60 |
| 1983-07-30 | @ TOR | 100 | L 5-6 | 40-60 | 7 | 23,445 | Neal Heaton | Dave Stieb | Joey McLaughlin | Bud Anderson | | 431 | 492 | -61 |
| 1983-07-31 | @ TOR | 101 | W 16-11 | 41-60 | 7 | 22,498 | Lary Sorensen | Jim Gott | Juan Eichelberger | Jim Acker | Bud Anderson | 447 | 503 | -56 |
| 1983-08-01 | @ TOR | 102 | W 6-0 | 42-60 | 7 | 20,781 | Len Barker | Doyle Alexander | Len Barker | Doyle Alexander | | 453 | 503 | -50 |
| 1983-08-02 | vs BAL | 103 | W 3-1 | 44-60 | 7 | 0 | Bert Blyleven | Dennis Martinez | Bert Blyleven | Dennis Martinez | Bud Anderson | 456 | 504 | -48 |
| 1983-08-02 | vs BAL | 104 | W 4-3 | 44-60 | 7 | 17,286 | Tom Brennan | Allan Ramirez | Tom Brennan | Allan Ramirez | Bud Anderson | 460 | 507 | -47 |
| 1983-08-03 | vs BAL | 105 | L 2-8 | 44-61 | 7 | 8,549 | Rick Sutcliffe | Storm Davis | Storm Davis | Rick Sutcliffe | | 462 | 515 | -53 |
| 1983-08-04 | vs BAL | 106 | L 3-4 | 44-62 | 7 | 6,368 | Neal Heaton | Scott McGregor | Scott McGregor | Bud Anderson | Tippy Martinez | 465 | 519 | -54 |
| 1983-08-05 | vs TEX | 107 | L 0-2 | 44-63 | 7 | 10,303 | Lary Sorensen | Mike Smithson | Mike Smithson | Lary Sorensen | Odell Jones | 465 | 521 | -56 |
| 1983-08-06 | vs TEX | 108 | L 1-6 | 44-64 | 7 | 13,866 | Len Barker | Frank Tanana | Frank Tanana | Len Barker | | 466 | 527 | -61 |
| 1983-08-07 | vs TEX | 109 | L 3-4 | 45-65 | 7 | 0 | Bert Blyleven | Charlie Hough | Charlie Hough | Dan Spillner | Victor Cruz | 469 | 531 | -62 |
| 1983-08-07 | vs TEX | 110 | W 7-0 | 45-65 | 7 | 19,213 | Tom Brennan | Jon Matlack | Tom Brennan | Jon Matlack | | 476 | 531 | -55 |
| 1983-08-08 | @ BAL | 111 | W 9-4 | 46-65 | 7 | 24,324 | Rick Sutcliffe | Storm Davis | Rick Sutcliffe | Storm Davis | | 485 | 535 | -50 |
| 1983-08-09 | @ BAL | 112 | W 4-3 | 47-65 | 7 | 19,026 | Neal Heaton | Scott McGregor | Neal Heaton | Scott McGregor | | 489 | 538 | -49 |
| 1983-08-10 | @ BAL | 113 | W 4-3 | 48-65 | 7 | 18,294 | Lary Sorensen | Mike Boddicker | Lary Sorensen | Mike Boddicker | | 493 | 541 | -48 |
| 1983-08-12 | @ TEX | 114 | L 2-6 | 48-66 | 7 | 19,310 | Tom Brennan | Frank Tanana | Frank Tanana | Tom Brennan | Odell Jones | 495 | 547 | -52 |
| 1983-08-13 | @ TEX | 115 | L 3-4 | 48-67 | 7 | 32,563 | Rick Sutcliffe | Charlie Hough | Charlie Hough | Rick Sutcliffe | Victor Cruz | 498 | 551 | -53 |
| 1983-08-14 | @ TEX | 116 | W 3-0 | 49-67 | 7 | 12,957 | Neal Heaton | Rick Honeycutt | Neal Heaton | Rick Honeycutt | | 501 | 551 | -50 |
| 1983-08-15 | vs TOR | 117 | L 2-3 | 49-68 | 7 | 6,675 | Lary Sorensen | Jim Gott | Randy Moffitt | Dan Spillner | | 503 | 554 | -51 |
| 1983-08-16 | vs TOR | 118 | W 3-2 | 50-69 | 7 | 0 | Len Barker | Doyle Alexander | Jamie Easterly | Randy Moffitt | | 506 | 556 | -50 |
| 1983-08-16 | vs TOR | 119 | L 6-9 | 50-69 | 7 | 9,666 | Tom Brennan | Matt Williams | Joey McLaughlin | Bud Anderson | | 512 | 565 | -53 |
| 1983-08-17 | vs TOR | 120 | L 5-6 | 50-70 | 7 | 6,239 | Rick Sutcliffe | Luis Leal | Joey McLaughlin | Rick Sutcliffe | Roy Lee Jackson | 517 | 571 | -54 |
| 1983-08-19 | vs SEA | 121 | W 6-5 | 51-70 | 7 | 6,639 | Neal Heaton | Bryan Clark | Neal Heaton | Karl Best | Jamie Easterly | 523 | 576 | -53 |
| 1983-08-20 | vs SEA | 122 | W 3-2 | 52-70 | 7 | 6,001 | Lary Sorensen | Jim Beattie | Jamie Easterly | Jim Beattie | | 526 | 578 | -52 |
| 1983-08-21 | vs SEA | 123 | L 2-7 | 52-71 | 7 | 10,259 | Mike Jeffcoat | Glenn Abbott | Glenn Abbott | Mike Jeffcoat | Mike Stanton | 528 | 585 | -57 |
| 1983-08-22 | vs CAL | 124 | L 3-7 | 52-72 | 7 | 6,184 | Rick Sutcliffe | Rick Steirer | Bruce Kison | Dan Spillner | | 531 | 592 | -61 |
| 1983-08-23 | vs CAL | 125 | L 2-5 | 52-73 | 7 | 7,001 | Len Barker | Mike Witt | Mike Witt | Len Barker | Luis Sanchez | 533 | 597 | -64 |
| 1983-08-24 | vs OAK | 126 | W 1-0 | 54-73 | 7 | 0 | Neal Heaton | Tim Conroy | Neal Heaton | Tim Conroy | | 534 | 597 | -63 |
| 1983-08-24 | vs OAK | 127 | W 4-2 | 54-73 | 7 | 6,096 | Lary Sorensen | Mark Smith | Lary Sorensen | Keith Atherton | Jamie Easterly | 538 | 599 | -61 |
| 1983-08-25 | vs OAK | 128 | L 0-6 | 54-74 | 7 | 6,044 | Mike Jeffcoat | Steve McCatty | Steve McCatty | Mike Jeffcoat | | 538 | 605 | -67 |
| 1983-08-26 | @ SEA | 129 | W 4-1 | 55-74 | 7 | 5,581 | Rick Sutcliffe | Bob Stoddard | Rick Sutcliffe | Bob Stoddard | | 542 | 606 | -64 |
| 1983-08-27 | @ SEA | 130 | L 3-6 | 55-75 | 7 | 7,409 | Juan Eichelberger | Matt Young | Matt Young | Juan Eichelberger | Mike Stanton | 545 | 612 | -67 |
| 1983-08-28 | @ SEA | 131 | W 5-2 | 56-75 | 7 | 7,474 | Lary Sorensen | Mike Moore | Lary Sorensen | Mike Moore | | 550 | 614 | -64 |
| 1983-08-29 | @ CAL | 132 | W 6-4 | 57-75 | 7 | 22,134 | Neal Heaton | Mike Witt | Neal Heaton | Mike Witt | Bud Anderson | 556 | 618 | -62 |
| 1983-08-30 | @ CAL | 133 | L 6-10 | 57-76 | 7 | 22,187 | Rick Sutcliffe | Tommy John | Rick Steirer | Mike Jeffcoat | | 562 | 628 | -66 |
| 1983-08-31 | @ CAL | 134 | W 7-5 | 58-76 | 7 | 22,659 | Bert Blyleven | Geoff Zahn | Rick Sutcliffe | Luis Sanchez | Jamie Easterly | 569 | 633 | -64 |
| 1983-09-02 | @ OAK | 135 | W 4-2 | 59-76 | 7 | 6,916 | Lary Sorensen | Gorman Heimueller | Lary Sorensen | Gorman Heimueller | Bud Anderson | 573 | 635 | -62 |
| 1983-09-03 | @ OAK | 136 | W 13-6 | 60-76 | 7 | 15,196 | Neal Heaton | Mike Warren | Dan Spillner | Dave Beard | | 586 | 641 | -55 |
| 1983-09-04 | @ OAK | 137 | W 9-2 | 61-76 | 7 | 10,274 | Rick Sutcliffe | Steve McCatty | Rick Sutcliffe | Steve McCatty | | 595 | 643 | -48 |
| 1983-09-05 | vs DET | 138 | W 3-2 | 62-76 | 7 | 5,593 | Bert Blyleven | Jack Morris | Bud Anderson | Jack Morris | | 598 | 645 | -47 |
| 1983-09-07 | vs DET | 139 | W 7-1 | 63-77 | 7 | 0 | Lary Sorensen | Milt Wilcox | Lary Sorensen | Milt Wilcox | | 605 | 646 | -41 |
| 1983-09-07 | vs DET | 140 | L 3-7 | 63-77 | 7 | 7,046 | Rick Behenna | Dan Petry | Dan Petry | Ernie Camacho | | 608 | 653 | -45 |
| 1983-09-09 | vs BOS | 141 | L 4-6 | 63-78 | 7 | 7,822 | Neal Heaton | John Tudor | John Tudor | Neal Heaton | Bob Stanley | 612 | 659 | -47 |
| 1983-09-10 | vs BOS | 142 | W 8-6 | 64-78 | 7 | 9,786 | Rick Sutcliffe | Bruce Hurst | Rich Barnes | Doug Bird | Bud Anderson | 620 | 665 | -45 |
| 1983-09-11 | vs BOS | 143 | L 1-4 | 64-79 | 7 | 6,554 | Lary Sorensen | Bob Ojeda | Bob Ojeda | Lary Sorensen | | 621 | 669 | -48 |
| 1983-09-12 | @ DET | 144 | L 1-5 | 64-80 | 7 | 13,535 | Bert Blyleven | Milt Wilcox | Milt Wilcox | Bert Blyleven | | 622 | 674 | -52 |
| 1983-09-13 | @ DET | 145 | L 2-3 | 64-81 | 7 | 14,302 | Rick Behenna | Jack Morris | Jack Morris | Rick Behenna | | 624 | 677 | -53 |
| 1983-09-14 | @ DET | 146 | L 0-5 | 64-82 | 7 | 13,208 | Rick Sutcliffe | Glenn Abbott | Glenn Abbott | Rick Sutcliffe | | 624 | 682 | -58 |
| 1983-09-17 | vs NYA | 147 | W 7-6 | 65-82 | 7 | 12,470 | Neal Heaton | Shane Rawley | Jamie Easterly | George Frazier | | 631 | 688 | -57 |
| 1983-09-18 | vs NYA | 148 | W 10-6 | 66-83 | 7 | 0 | Lary Sorensen | Dave Righetti | Mike Jeffcoat | Dave Righetti | | 641 | 694 | -53 |
| 1983-09-18 | vs NYA | 149 | L 8-13 | 66-83 | 7 | 15,048 | Rich Barnes | Ray Fontenot | Ray Fontenot | Rick Behenna | | 649 | 707 | -58 |
| 1983-09-20 | vs MIL | 150 | L 7-11 | 66-84 | 7 | 6,218 | Rick Sutcliffe | Mike Caldwell | Jim Slaton | Bud Anderson | Pete Ladd | 656 | 718 | -62 |
| 1983-09-21 | vs MIL | 151 | L 7-10 | 66-85 | 7 | 4,135 | Neal Heaton | Don Sutton | Don Sutton | Neal Heaton | Pete Ladd | 663 | 728 | -65 |
| 1983-09-22 | vs MIL | 152 | W 9-5 | 67-85 | 7 | 5,456 | Lary Sorensen | Tom Candiotti | Lary Sorensen | Tom Candiotti | | 672 | 733 | -61 |
| 1983-09-23 | @ NYA | 153 | L 4-7 | 67-86 | 7 | 26,204 | Rick Behenna | Shane Rawley | George Frazier | Jamie Easterly | | 676 | 740 | -64 |
| 1983-09-24 | @ NYA | 154 | L 1-9 | 67-87 | 7 | 30,202 | Rick Sutcliffe | Ron Guidry | Ron Guidry | Rick Sutcliffe | | 677 | 749 | -72 |
| 1983-09-25 | @ NYA | 155 | L 4-6 | 67-88 | 7 | 31,303 | Rich Barnes | John Montefusco | John Montefusco | Rich Barnes | Rich Gossage | 681 | 755 | -74 |
| 1983-09-26 | @ NYA | 156 | W 7-0 | 68-88 | 7 | 15,119 | Neal Heaton | Bob Shirley | Neal Heaton | Bob Shirley | | 688 | 755 | -67 |
| 1983-09-27 | @ MIL | 157 | L 4-8 | 68-89 | 7 | 11,514 | Lary Sorensen | Mike Caldwell | Mike Caldwell | Lary Sorensen | | 692 | 763 | -71 |
| 1983-09-28 | @ MIL | 158 | L 4-6 | 68-90 | 7 | 11,976 | Rick Behenna | Don Sutton | Jim Slaton | Jamie Easterly | | 696 | 769 | -73 |
| 1983-09-29 | @ MIL | 159 | W 4-2 | 69-90 | 7 | 15,331 | Rick Sutcliffe | Tom Candiotti | Rick Sutcliffe | Tom Candiotti | | 700 | 771 | -71 |
| 1983-09-30 | @ BOS | 160 | L 0-10 | 69-91 | 7 | 18,928 | Neal Heaton | Dennis Eckersley | Dennis Eckersley | Neal Heaton | | 700 | 781 | -81 |
| 1983-10-01 | @ BOS | 161 | W 3-1 | 70-91 | 7 | 33,491 | Lary Sorensen | Oil Can Boyd | Lary Sorensen | Oil Can Boyd | | 703 | 782 | -79 |
| 1983-10-02 | @ BOS | 162 | L 1-3 | 70-92 | 7 | 33,491 | Bud Anderson | Al Nipper | Al Nipper | Bud Anderson | | 704 | 785 | -81 |