| 2004-04-04 | vs BOS | 1 | W 7-2 | 1-0 | 1 | 47,683 | Sidney Ponson | Pedro Martinez | Sidney Ponson | Pedro Martinez | B.J. Ryan | 7 | 2 | 5 |
| 2004-04-06 | vs BOS | 2 | L 1-4 | 1-1 | 2 | 35,355 | Eric DuBose | Curt Schilling | Curt Schilling | Eric DuBose | Keith Foulke | 8 | 6 | 2 |
| 2004-04-07 | vs BOS | 3 | L 3-10 | 1-2 | 4 | 28,373 | Kurt Ainsworth | Derek Lowe | Derek Lowe | Kurt Ainsworth | | 11 | 16 | -5 |
| 2004-04-08 | vs BOS | 4 | W 3-2 | 2-2 | 2 | 31,121 | Matt Riley | Tim Wakefield | Rodrigo Lopez | Bobby Jones | | 14 | 18 | -4 |
| 2004-04-09 | @ TBA | 5 | L 3-4 | 2-3 | 3 | 12,123 | Sidney Ponson | Mark Hendrickson | Danys Baez | John Parrish | | 17 | 22 | -5 |
| 2004-04-10 | @ TBA | 6 | W 11-3 | 3-3 | 1 | 14,093 | Erik Bedard | Geremi Gonzalez | Rick Bauer | Geremi Gonzalez | | 28 | 25 | 3 |
| 2004-04-11 | @ TBA | 7 | L 1-10 | 3-4 | 4 | 10,269 | Eric DuBose | Victor Zambrano | Victor Zambrano | Eric DuBose | | 29 | 35 | -6 |
| 2004-04-15 | @ BOS | 8 | W 12-7 | 4-4 | 2 | 35,271 | Sidney Ponson | Pedro Martinez | Buddy Groom | Bronson Arroyo | | 41 | 42 | -1 |
| 2004-04-16 | @ TOR | 9 | W 11-2 | 5-4 | 1 | 14,239 | Matt Riley | Miguel Batista | Matt Riley | Miguel Batista | | 52 | 44 | 8 |
| 2004-04-17 | @ TOR | 10 | W 5-3 | 6-4 | 1 | 20,177 | Kurt Ainsworth | Josh Towers | B.J. Ryan | Justin Speier | Jorge Julio | 57 | 47 | 10 |
| 2004-04-18 | @ TOR | 11 | W 7-0 | 7-4 | 1 | 16,842 | Eric DuBose | Pat Hentgen | Eric DuBose | Pat Hentgen | | 64 | 47 | 17 |
| 2004-04-20 | vs TBA | 12 | W 9-1 | 8-4 | 1 | 21,902 | Sidney Ponson | Mark Hendrickson | Sidney Ponson | Mark Hendrickson | | 73 | 48 | 25 |
| 2004-04-21 | vs TBA | 13 | L 3-7 | 8-5 | 2 | 20,781 | Matt Riley | Paul Abbott | Paul Abbott | Matt Riley | | 76 | 55 | 21 |
| 2004-04-22 | vs TBA | 14 | W 7-6 | 9-5 | 1 | 19,250 | Kurt Ainsworth | Damian Moss | John Parrish | Chad Gaudin | Jorge Julio | 83 | 61 | 22 |
| 2004-04-23 | vs TOR | 15 | W 11-3 | 10-5 | 1 | 26,827 | Eric DuBose | Josh Towers | Eric DuBose | Josh Towers | | 94 | 64 | 30 |
| 2004-04-24 | vs TOR | 16 | L 4-5 | 10-6 | 2 | 41,093 | Erik Bedard | Pat Hentgen | Kerry Ligtenberg | Mike DeJean | | 98 | 69 | 29 |
| 2004-04-25 | vs TOR | 17 | L 3-15 | 10-7 | 2 | 31,028 | Sidney Ponson | Roy Halladay | Roy Halladay | Sidney Ponson | | 101 | 84 | 17 |
| 2004-04-27 | vs SEA | 18 | L 5-7 | 10-8 | 2 | 19,747 | Matt Riley | Gil Meche | Ron Villone | Rodrigo Lopez | Eddie Guardado | 106 | 91 | 15 |
| 2004-04-28 | vs SEA | 19 | W 3-1 | 11-8 | 2 | 20,445 | Kurt Ainsworth | Jamie Moyer | John Parrish | Shigetoshi Hasegawa | Jorge Julio | 109 | 92 | 17 |
| 2004-04-29 | vs SEA | 20 | W 9-5 | 12-8 | 2 | 24,792 | Eric DuBose | Joel Pineiro | Eric DuBose | Joel Pineiro | | 118 | 97 | 21 |
| 2004-04-30 | @ CLE | 21 | L 2-11 | 12-9 | 2 | 18,782 | Sidney Ponson | Cliff Lee | Cliff Lee | Sidney Ponson | | 120 | 108 | 12 |
| 2004-05-01 | @ CLE | 22 | L 2-3 | 12-10 | 2 | 17,275 | Erik Bedard | CC Sabathia | Chad Durbin | Mike DeJean | | 122 | 111 | 11 |
| 2004-05-03 | vs CHA | 23 | L 4-5 | 12-11 | 3 | 18,849 | Kurt Ainsworth | Scott Schoeneweis | Scott Schoeneweis | Mike DeJean | Billy Koch | 126 | 116 | 10 |
| 2004-05-04 | vs CHA | 24 | W 10-3 | 13-11 | 3 | 21,488 | Eric DuBose | Esteban Loaiza | Rodrigo Lopez | Esteban Loaiza | | 136 | 119 | 17 |
| 2004-05-05 | vs CHA | 25 | L 5-6 | 13-12 | 3 | 20,978 | Sidney Ponson | Mark Buehrle | Shingo Takatsu | B.J. Ryan | Billy Koch | 141 | 125 | 16 |
| 2004-05-07 | vs CLE | 26 | W 3-2 | 14-12 | 3 | 34,324 | Erik Bedard | Cliff Lee | Jorge Julio | Chad Durbin | | 144 | 127 | 17 |
| 2004-05-08 | vs CLE | 27 | W 10-7 | 15-12 | 3 | 30,687 | Kurt Ainsworth | Jake Westbrook | John Parrish | Scott Stewart | Jorge Julio | 154 | 134 | 20 |
| 2004-05-09 | vs CLE | 28 | W 12-11 | 16-12 | 3 | 35,778 | Eric DuBose | Jason Davis | Rodrigo Lopez | David Riske | Jorge Julio | 166 | 145 | 21 |
| 2004-05-11 | @ CHA | 29 | L 0-15 | 16-13 | 3 | 20,400 | Sidney Ponson | Mark Buehrle | Mark Buehrle | Sidney Ponson | | 166 | 160 | 6 |
| 2004-05-13 | @ CHA | 30 | W 1-0 | 17-14 | 3 | 0 | Daniel Cabrera | Jon Garland | Daniel Cabrera | Jon Garland | Jorge Julio | 167 | 160 | 7 |
| 2004-05-13 | @ CHA | 31 | L 5-6 | 17-14 | 3 | 18,324 | Erik Bedard | Felix Diaz | Michael Jackson | Erik Bedard | Billy Koch | 172 | 166 | 6 |
| 2004-05-14 | vs ANA | 32 | L 9-10 | 17-15 | 3 | 38,232 | Kurt Ainsworth | Bartolo Colon | Troy Percival | Jorge Julio | Scot Shields | 181 | 176 | 5 |
| 2004-05-15 | vs ANA | 33 | L 4-7 | 17-16 | 3 | 40,275 | Eric DuBose | Jarrod Washburn | Jarrod Washburn | Eric DuBose | Troy Percival | 185 | 183 | 2 |
| 2004-05-16 | vs ANA | 34 | W 4-0 | 18-16 | 3 | 25,448 | Sidney Ponson | Kelvim Escobar | Sidney Ponson | Kelvim Escobar | | 189 | 183 | 6 |
| 2004-05-18 | @ SEA | 35 | W 7-2 | 19-16 | 3 | 29,819 | Daniel Cabrera | Freddy Garcia | Daniel Cabrera | Freddy Garcia | | 196 | 185 | 11 |
| 2004-05-19 | @ SEA | 36 | W 5-2 | 20-16 | 3 | 29,575 | Erik Bedard | Ryan Franklin | Erik Bedard | Ryan Franklin | Jorge Julio | 201 | 187 | 14 |
| 2004-05-20 | @ SEA | 37 | L 0-11 | 20-17 | 3 | 27,967 | Rodrigo Lopez | Jamie Moyer | Jamie Moyer | Rodrigo Lopez | | 201 | 198 | 3 |
| 2004-05-21 | @ ANA | 38 | L 3-5 | 20-18 | 3 | 43,557 | Eric DuBose | Jarrod Washburn | Scot Shields | Mike DeJean | Troy Percival | 204 | 203 | 1 |
| 2004-05-22 | @ ANA | 39 | L 2-3 | 20-19 | 3 | 43,586 | Sidney Ponson | Kelvim Escobar | Kelvim Escobar | Sidney Ponson | Troy Percival | 206 | 206 | 0 |
| 2004-05-23 | @ ANA | 40 | L 3-8 | 20-20 | 3 | 43,758 | Daniel Cabrera | Aaron Sele | Aaron Sele | Daniel Cabrera | | 209 | 214 | -5 |
| 2004-05-25 | vs NYA | 41 | L 3-11 | 20-21 | 3 | 42,846 | Erik Bedard | Jon Lieber | Jon Lieber | Erik Bedard | | 212 | 225 | -13 |
| 2004-05-26 | vs NYA | 42 | L 9-12 | 20-22 | 3 | 37,610 | Rodrigo Lopez | Mike Mussina | Tanyon Sturtze | B.J. Ryan | Mariano Rivera | 221 | 237 | -16 |
| 2004-05-27 | vs NYA | 43 | L 5-18 | 20-23 | 3 | 46,282 | Sidney Ponson | Jose Contreras | Jose Contreras | Sidney Ponson | | 226 | 255 | -29 |
| 2004-05-28 | @ DET | 44 | W 7-5 | 21-23 | 3 | 23,298 | Eric DuBose | Jason Johnson | Eric DuBose | Jason Johnson | Jorge Julio | 233 | 260 | -27 |
| 2004-05-29 | @ DET | 45 | W 8-4 | 22-23 | 3 | 30,440 | Daniel Cabrera | Jeremy Bonderman | Daniel Cabrera | Jeremy Bonderman | John Parrish | 241 | 264 | -23 |
| 2004-05-30 | @ DET | 46 | W 7-3 | 23-23 | 3 | 25,337 | Erik Bedard | Mike Maroth | Buddy Groom | Ugueth Urbina | | 248 | 267 | -19 |
| 2004-05-31 | @ BOS | 47 | W 13-4 | 24-23 | 3 | 35,465 | Rodrigo Lopez | Derek Lowe | Rodrigo Lopez | Derek Lowe | | 261 | 271 | -10 |
| 2004-06-01 | @ NYA | 48 | L 7-8 | 24-24 | 3 | 38,012 | Sidney Ponson | Mike Mussina | Mike Mussina | Sidney Ponson | Mariano Rivera | 268 | 279 | -11 |
| 2004-06-02 | @ NYA | 49 | L 5-6 | 24-25 | 3 | 50,502 | Eric DuBose | Jose Contreras | Bret Prinz | Eric DuBose | Mariano Rivera | 273 | 285 | -12 |
| 2004-06-03 | @ NYA | 50 | L 2-5 | 24-26 | 3 | 44,020 | Daniel Cabrera | Javier Vazquez | Javier Vazquez | John Parrish | Mariano Rivera | 275 | 290 | -15 |
| 2004-06-04 | vs TBA | 51 | L 7-8 | 24-27 | 3 | 32,139 | Erik Bedard | Victor Zambrano | Lance Carter | Mike DeJean | Danys Baez | 282 | 298 | -16 |
| 2004-06-06 | vs TBA | 52 | W 5-4 | 25-27 | 3 | 46,044 | Rodrigo Lopez | Rob Bell | Rodrigo Lopez | Rob Bell | Jorge Julio | 287 | 302 | -15 |
| 2004-06-08 | vs ARI | 53 | L 1-8 | 25-28 | 3 | 28,927 | Sidney Ponson | Randy Johnson | Randy Johnson | Sidney Ponson | | 288 | 310 | -22 |
| 2004-06-09 | vs ARI | 54 | W 8-2 | 26-28 | 3 | 25,776 | Eric DuBose | Brandon Webb | John Parrish | Steve Randolph | | 296 | 312 | -16 |
| 2004-06-10 | vs ARI | 55 | L 0-3 | 26-29 | 3 | 25,106 | Daniel Cabrera | Casey Fossum | Casey Fossum | Daniel Cabrera | Jose Valverde | 296 | 315 | -19 |
| 2004-06-12 | vs SFN | 56 | L 6-9 | 27-30 | 3 | 48,869 | Rodrigo Lopez | Dustin Hermanson | Matt Herges | Jorge Julio | | 302 | 324 | -22 |
| 2004-06-12 | vs SFN | 57 | W 5-4 | 27-30 | 3 | 40,434 | Erik Bedard | Noah Lowry | John Parrish | Scott Eyre | | 307 | 328 | -21 |
| 2004-06-13 | vs SFN | 58 | L 3-7 | 27-31 | 3 | 45,728 | Sidney Ponson | Jerome Williams | Jerome Williams | Sidney Ponson | Tyler Walker | 310 | 335 | -25 |
| 2004-06-14 | @ CLE | 59 | L 0-14 | 27-32 | 3 | 19,340 | Eric DuBose | Jake Westbrook | Jake Westbrook | Eric DuBose | | 310 | 349 | -39 |
| 2004-06-15 | @ LAN | 60 | L 1-5 | 27-33 | 3 | 29,711 | Daniel Cabrera | Jose Lima | Jose Lima | Daniel Cabrera | Eric Gagne | 311 | 354 | -43 |
| 2004-06-16 | @ LAN | 61 | L 3-6 | 27-34 | 4 | 35,070 | Matt Riley | Odalis Perez | Odalis Perez | Matt Riley | Eric Gagne | 314 | 360 | -46 |
| 2004-06-17 | @ LAN | 62 | L 3-4 | 27-35 | 4 | 30,465 | Erik Bedard | Kazuhisa Ishii | Guillermo Mota | Rodrigo Lopez | Eric Gagne | 317 | 364 | -47 |
| 2004-06-18 | @ COL | 63 | L 3-5 | 27-36 | 5 | 30,148 | Sidney Ponson | Shawn Estes | Shawn Estes | Sidney Ponson | Shawn Chacon | 320 | 369 | -49 |
| 2004-06-19 | @ COL | 64 | L 6-11 | 27-37 | 5 | 33,326 | Eric DuBose | Jeff Fassero | Jeff Fassero | Eric DuBose | | 326 | 380 | -54 |
| 2004-06-20 | @ COL | 65 | W 4-2 | 28-37 | 5 | 40,532 | Daniel Cabrera | Joe Kennedy | B.J. Ryan | Shawn Chacon | Jorge Julio | 330 | 382 | -52 |
| 2004-06-22 | vs NYA | 66 | L 4-10 | 28-38 | 5 | 49,696 | Matt Riley | Mike Mussina | Mike Mussina | Matt Riley | | 334 | 392 | -58 |
| 2004-06-23 | vs NYA | 67 | W 13-2 | 29-38 | 5 | 41,678 | Erik Bedard | Jon Lieber | Erik Bedard | Jon Lieber | | 347 | 394 | -47 |
| 2004-06-24 | vs NYA | 68 | L 2-5 | 29-39 | 5 | 48,442 | Sidney Ponson | Javier Vazquez | Javier Vazquez | Sidney Ponson | Mariano Rivera | 349 | 399 | -50 |
| 2004-06-25 | vs ATL | 69 | W 5-0 | 30-39 | 5 | 33,579 | Daniel Cabrera | Paul Byrd | Daniel Cabrera | Paul Byrd | | 354 | 399 | -45 |
| 2004-06-26 | vs ATL | 70 | L 0-5 | 30-40 | 5 | 47,438 | Rodrigo Lopez | Russ Ortiz | Russ Ortiz | Rodrigo Lopez | John Smoltz | 354 | 404 | -50 |
| 2004-06-27 | vs ATL | 71 | L 7-8 | 30-41 | 5 | 39,095 | Matt Riley | Jaret Wright | Juan Cruz | Jason Grimsley | John Smoltz | 361 | 412 | -51 |
| 2004-06-28 | @ KCA | 72 | W 10-1 | 31-41 | 5 | 14,521 | Erik Bedard | Darrell May | Erik Bedard | Darrell May | | 371 | 413 | -42 |
| 2004-06-29 | @ KCA | 73 | L 3-4 | 31-42 | 5 | 15,575 | Sidney Ponson | Mike Wood | Mike Wood | Sidney Ponson | Shawn Camp | 374 | 417 | -43 |
| 2004-06-30 | @ KCA | 74 | W 13-4 | 32-42 | 5 | 14,970 | Daniel Cabrera | Brian Anderson | Daniel Cabrera | Brian Anderson | | 387 | 421 | -34 |
| 2004-07-01 | @ KCA | 75 | W 3-2 | 33-42 | 5 | 22,960 | Rodrigo Lopez | Zack Greinke | Rodrigo Lopez | Zack Greinke | Jorge Julio | 390 | 423 | -33 |
| 2004-07-02 | @ PHI | 76 | W 7-6 | 34-42 | 4 | 44,390 | Matt Riley | Brett Myers | Eddy Rodriguez | Brian Powell | Daniel Cabrera | 397 | 429 | -32 |
| 2004-07-03 | @ PHI | 77 | L 6-7 | 34-43 | 5 | 44,163 | Erik Bedard | Kevin Millwood | Rheal Cormier | Jason Grimsley | Billy Wagner | 403 | 436 | -33 |
| 2004-07-04 | @ PHI | 78 | L 2-5 | 34-44 | 5 | 43,396 | Sidney Ponson | Eric Milton | Eric Milton | Sidney Ponson | Tim Worrell | 405 | 441 | -36 |
| 2004-07-05 | vs TBA | 79 | W 4-2 | 36-44 | 4 | 31,438 | Daniel Cabrera | Dewon Brazelton | B.J. Ryan | Dewon Brazelton | Jorge Julio | 409 | 443 | -34 |
| 2004-07-05 | vs TBA | 80 | W 8-2 | 36-44 | 4 | 26,727 | Dave Borkowski | Geremi Gonzalez | Dave Borkowski | Geremi Gonzalez | | 417 | 445 | -28 |
| 2004-07-06 | vs TBA | 81 | L 1-3 | 36-45 | 5 | 22,192 | Rodrigo Lopez | Mark Hendrickson | Mark Hendrickson | Rodrigo Lopez | Danys Baez | 418 | 448 | -30 |
| 2004-07-07 | vs TBA | 82 | L 3-13 | 36-46 | 5 | 28,081 | John Parrish | Rob Bell | Rob Bell | John Parrish | | 421 | 461 | -40 |
| 2004-07-09 | vs KCA | 83 | L 0-7 | 36-47 | 5 | 43,947 | Erik Bedard | Darrell May | Darrell May | Erik Bedard | | 421 | 468 | -47 |
| 2004-07-10 | vs KCA | 84 | W 7-2 | 37-47 | 5 | 33,493 | Daniel Cabrera | Mike Wood | Daniel Cabrera | Mike Wood | | 428 | 470 | -42 |
| 2004-07-11 | vs KCA | 85 | L 7-11 | 37-48 | 5 | 31,042 | Rodrigo Lopez | Jimmy Gobble | Jimmy Gobble | Rodrigo Lopez | | 435 | 481 | -46 |
| 2004-07-15 | @ TBA | 86 | W 5-4 | 38-48 | 5 | 16,185 | Daniel Cabrera | Victor Zambrano | Daniel Cabrera | Travis Harper | Jorge Julio | 440 | 485 | -45 |
| 2004-07-16 | @ TBA | 87 | L 0-2 | 38-49 | 5 | 20,960 | Erik Bedard | John Halama | John Halama | Erik Bedard | Danys Baez | 440 | 487 | -47 |
| 2004-07-17 | @ TBA | 88 | W 3-2 | 39-49 | 4 | 18,571 | Rodrigo Lopez | Dewon Brazelton | Rodrigo Lopez | Dewon Brazelton | Jorge Julio | 443 | 489 | -46 |
| 2004-07-18 | @ TBA | 89 | L 2-7 | 39-50 | 4 | 13,656 | Dave Borkowski | Mark Hendrickson | Mark Hendrickson | Dave Borkowski | | 445 | 496 | -51 |
| 2004-07-19 | @ KCA | 90 | W 7-4 | 40-50 | 4 | 17,586 | Sidney Ponson | Brian Anderson | Sidney Ponson | Brian Anderson | | 452 | 500 | -48 |
| 2004-07-20 | @ KCA | 91 | W 12-3 | 41-50 | 4 | 18,225 | Daniel Cabrera | Zack Greinke | Daniel Cabrera | Zack Greinke | | 464 | 503 | -39 |
| 2004-07-21 | @ BOS | 92 | W 10-5 | 42-50 | 4 | 35,023 | Erik Bedard | Pedro Martinez | Erik Bedard | Pedro Martinez | | 474 | 508 | -34 |
| 2004-07-22 | @ BOS | 93 | W 8-3 | 43-51 | 4 | 34,697 | Rodrigo Lopez | Abe Alvarez | Rodrigo Lopez | Abe Alvarez | | 482 | 511 | -29 |
| 2004-07-22 | @ BOS | 94 | L 0-4 | 43-51 | 4 | 35,370 | Dave Borkowski | Tim Wakefield | Tim Wakefield | Dave Borkowski | | 482 | 515 | -33 |
| 2004-07-23 | vs MIN | 95 | L 3-7 | 43-52 | 4 | 34,874 | John Maine | Carlos Silva | Carlos Silva | John Maine | | 485 | 522 | -37 |
| 2004-07-24 | vs MIN | 96 | W 4-2 | 44-52 | 4 | 36,652 | Sidney Ponson | Terry Mulholland | Sidney Ponson | Joe Roa | Jorge Julio | 489 | 524 | -35 |
| 2004-07-25 | vs MIN | 97 | L 4-8 | 44-53 | 4 | 41,833 | Daniel Cabrera | Kyle Lohse | Kyle Lohse | Daniel Cabrera | | 493 | 532 | -39 |
| 2004-07-26 | vs BOS | 98 | L 5-12 | 44-54 | 4 | 42,113 | Erik Bedard | Pedro Martinez | Pedro Martinez | Erik Bedard | | 498 | 544 | -46 |
| 2004-07-28 | vs BOS | 99 | W 4-1 | 45-54 | 4 | 45,780 | Dave Borkowski | Curt Schilling | Dave Borkowski | Curt Schilling | | 502 | 545 | -43 |
| 2004-07-29 | @ NYA | 100 | W 9-1 | 46-54 | 4 | 51,677 | Sidney Ponson | Jose Contreras | Sidney Ponson | Jose Contreras | | 511 | 546 | -35 |
| 2004-07-30 | @ NYA | 101 | L 1-2 | 46-55 | 4 | 51,551 | Daniel Cabrera | Kevin Brown | Kevin Brown | Daniel Cabrera | Mariano Rivera | 512 | 548 | -36 |
| 2004-07-31 | @ NYA | 102 | L 4-6 | 46-56 | 4 | 51,845 | Erik Bedard | Javier Vazquez | Javier Vazquez | Erik Bedard | Mariano Rivera | 516 | 554 | -38 |
| 2004-08-01 | @ NYA | 103 | L 7-9 | 46-57 | 4 | 51,632 | Rodrigo Lopez | Orlando Hernandez | Orlando Hernandez | Rodrigo Lopez | Mariano Rivera | 523 | 563 | -40 |
| 2004-08-03 | vs SEA | 104 | W 9-7 | 48-57 | 4 | 21,188 | Sidney Ponson | Ron Villone | Jason Grimsley | Clint Nageotte | Jorge Julio | 532 | 570 | -38 |
| 2004-08-03 | vs SEA | 105 | W 5-4 | 48-57 | 4 | 24,525 | Dave Borkowski | Jamie Moyer | Jorge Julio | George Sherrill | | 537 | 574 | -37 |
| 2004-08-04 | vs SEA | 106 | W 6-3 | 49-57 | 4 | 27,539 | Daniel Cabrera | Gil Meche | Todd Williams | Shigetoshi Hasegawa | Jorge Julio | 543 | 577 | -34 |
| 2004-08-06 | vs TEX | 107 | W 9-1 | 50-57 | 4 | 29,276 | Erik Bedard | Nick Regilio | Erik Bedard | Nick Regilio | | 552 | 578 | -26 |
| 2004-08-07 | vs TEX | 108 | W 3-1 | 51-57 | 4 | 44,961 | Rodrigo Lopez | Scott Erickson | Rodrigo Lopez | Scott Erickson | Jorge Julio | 555 | 579 | -24 |
| 2004-08-08 | vs TEX | 109 | W 11-5 | 52-57 | 4 | 32,842 | Sidney Ponson | Kenny Rogers | Sidney Ponson | Kenny Rogers | | 566 | 584 | -18 |
| 2004-08-09 | vs TEX | 110 | W 7-3 | 53-57 | 4 | 39,850 | Dave Borkowski | Michael Bacsik | Dave Borkowski | Michael Bacsik | | 573 | 587 | -14 |
| 2004-08-10 | @ ANA | 111 | W 11-3 | 54-57 | 3 | 43,068 | Daniel Cabrera | Aaron Sele | Daniel Cabrera | Aaron Sele | | 584 | 590 | -6 |
| 2004-08-11 | @ ANA | 112 | L 2-4 | 54-58 | 3 | 41,446 | Erik Bedard | Kelvim Escobar | Kelvim Escobar | Jason Grimsley | Troy Percival | 586 | 594 | -8 |
| 2004-08-12 | @ ANA | 113 | W 6-1 | 55-58 | 3 | 41,467 | Rodrigo Lopez | Bartolo Colon | Rodrigo Lopez | Bartolo Colon | | 592 | 595 | -3 |
| 2004-08-13 | @ TOR | 114 | W 4-0 | 56-58 | 3 | 21,234 | Sidney Ponson | Miguel Batista | Sidney Ponson | Miguel Batista | | 596 | 595 | 1 |
| 2004-08-14 | @ TOR | 115 | L 2-7 | 56-59 | 3 | 35,768 | Dave Borkowski | Josh Towers | Josh Towers | Dave Borkowski | | 598 | 602 | -4 |
| 2004-08-15 | @ TOR | 116 | W 11-7 | 57-59 | 3 | 26,132 | Daniel Cabrera | David Bush | Buddy Groom | Vinnie Chulk | | 609 | 609 | 0 |
| 2004-08-16 | vs OAK | 117 | L 1-3 | 57-60 | 3 | 40,964 | Erik Bedard | Mark Redman | Mark Redman | Erik Bedard | Octavio Dotel | 610 | 612 | -2 |
| 2004-08-17 | vs OAK | 118 | L 0-11 | 57-61 | 3 | 32,243 | Rodrigo Lopez | Tim Hudson | Tim Hudson | Rodrigo Lopez | | 610 | 623 | -13 |
| 2004-08-18 | vs OAK | 119 | L 4-5 | 57-62 | 3 | 40,603 | Sidney Ponson | Mark Mulder | Mark Mulder | B.J. Ryan | Octavio Dotel | 614 | 628 | -14 |
| 2004-08-20 | vs TOR | 120 | L 4-14 | 57-63 | 3 | 35,024 | Dave Borkowski | Josh Towers | Josh Towers | Dave Borkowski | | 618 | 642 | -24 |
| 2004-08-21 | vs TOR | 121 | L 4-10 | 57-64 | 3 | 38,079 | Daniel Cabrera | David Bush | David Bush | Daniel Cabrera | | 622 | 652 | -30 |
| 2004-08-22 | vs TOR | 122 | L 5-8 | 57-65 | 3 | 44,482 | Erik Bedard | Justin Miller | Justin Miller | Erik Bedard | Jason Frasor | 627 | 660 | -33 |
| 2004-08-23 | @ OAK | 123 | L 3-4 | 57-66 | 3 | 24,131 | Rodrigo Lopez | Tim Hudson | Tim Hudson | Buddy Groom | Octavio Dotel | 630 | 664 | -34 |
| 2004-08-24 | @ OAK | 124 | L 2-6 | 57-67 | 4 | 23,153 | Sidney Ponson | Mark Mulder | Mark Mulder | Sidney Ponson | | 632 | 670 | -38 |
| 2004-08-25 | @ OAK | 125 | L 0-3 | 57-68 | 4 | 35,260 | Bruce Chen | Rich Harden | Octavio Dotel | B.J. Ryan | | 632 | 673 | -41 |
| 2004-08-26 | @ OAK | 126 | L 4-9 | 57-69 | 4 | 22,404 | Daniel Cabrera | Barry Zito | Barry Zito | Daniel Cabrera | | 636 | 682 | -46 |
| 2004-08-27 | @ TEX | 127 | L 4-6 | 57-70 | 4 | 29,409 | Erik Bedard | John Wasdin | John Wasdin | Erik Bedard | Francisco Cordero | 640 | 688 | -48 |
| 2004-08-28 | @ TEX | 128 | L 3-4 | 57-71 | 4 | 41,676 | Rodrigo Lopez | Kenny Rogers | Frank Francisco | B.J. Ryan | Francisco Cordero | 643 | 692 | -49 |
| 2004-08-29 | @ TEX | 129 | W 7-6 | 58-71 | 4 | 30,577 | Sidney Ponson | Chris Young | Sidney Ponson | Chris Young | Jorge Julio | 650 | 698 | -48 |
| 2004-08-31 | @ TBA | 130 | W 10-6 | 59-71 | 3 | 8,620 | Bruce Chen | Rob Bell | Buddy Groom | Lance Carter | | 660 | 704 | -44 |
| 2004-09-01 | @ TBA | 131 | W 8-0 | 60-71 | 3 | 8,988 | Daniel Cabrera | Mark Hendrickson | Daniel Cabrera | Mark Hendrickson | | 668 | 704 | -36 |
| 2004-09-02 | @ TBA | 132 | W 13-2 | 61-71 | 3 | 9,019 | Erik Bedard | Dewon Brazelton | Erik Bedard | Dewon Brazelton | | 681 | 706 | -25 |
| 2004-09-03 | @ NYA | 133 | W 3-1 | 62-71 | 3 | 44,148 | Rodrigo Lopez | Kevin Brown | Rodrigo Lopez | Kevin Brown | Jorge Julio | 684 | 707 | -23 |
| 2004-09-04 | @ NYA | 134 | W 7-0 | 63-71 | 3 | 48,963 | Sidney Ponson | Mike Mussina | Sidney Ponson | Mike Mussina | | 691 | 707 | -16 |
| 2004-09-05 | @ NYA | 135 | L 3-4 | 63-72 | 3 | 48,252 | Bruce Chen | Javier Vazquez | Mariano Rivera | Jorge Julio | | 694 | 711 | -17 |
| 2004-09-06 | vs MIN | 136 | W 4-1 | 64-72 | 3 | 36,600 | Daniel Cabrera | Terry Mulholland | Daniel Cabrera | Terry Mulholland | Jorge Julio | 698 | 712 | -14 |
| 2004-09-07 | vs MIN | 137 | L 1-3 | 64-73 | 3 | 29,624 | Matt Riley | Brad Radke | J.C. Romero | Jorge Julio | Joe Nathan | 699 | 715 | -16 |
| 2004-09-08 | vs MIN | 138 | L 0-9 | 64-74 | 3 | 19,358 | Erik Bedard | Johan Santana | Johan Santana | Erik Bedard | | 699 | 724 | -25 |
| 2004-09-10 | vs NYA | 139 | W 14-8 | 65-74 | 3 | 48,026 | Rodrigo Lopez | Javier Vazquez | Rodrigo Lopez | Javier Vazquez | | 713 | 732 | -19 |
| 2004-09-11 | vs NYA | 140 | L 2-5 | 65-75 | 3 | 47,858 | Sidney Ponson | Orlando Hernandez | Orlando Hernandez | Sidney Ponson | Mariano Rivera | 715 | 737 | -22 |
| 2004-09-12 | vs NYA | 141 | L 7-9 | 65-76 | 3 | 47,780 | Daniel Cabrera | Jon Lieber | Tom Gordon | Jorge Julio | Mariano Rivera | 722 | 746 | -24 |
| 2004-09-13 | @ TOR | 142 | W 9-1 | 66-76 | 3 | 18,372 | Bruce Chen | Justin Miller | Bruce Chen | Justin Miller | | 731 | 747 | -16 |
| 2004-09-15 | @ TOR | 143 | L 0-3 | 66-77 | 3 | 19,942 | Matt Riley | Ted Lilly | Ted Lilly | Matt Riley | Justin Speier | 731 | 750 | -19 |
| 2004-09-16 | @ TOR | 144 | W 9-5 | 67-77 | 3 | 21,451 | Rodrigo Lopez | Miguel Batista | Rodrigo Lopez | Miguel Batista | | 740 | 755 | -15 |
| 2004-09-17 | @ MIN | 145 | W 11-2 | 68-77 | 3 | 21,675 | Sidney Ponson | Terry Mulholland | Sidney Ponson | Terry Mulholland | | 751 | 757 | -6 |
| 2004-09-18 | @ MIN | 146 | W 12-3 | 69-77 | 3 | 24,183 | Daniel Cabrera | Brad Radke | Daniel Cabrera | Brad Radke | | 763 | 760 | 3 |
| 2004-09-19 | @ MIN | 147 | L 1-5 | 69-78 | 3 | 31,399 | Bruce Chen | Johan Santana | Johan Santana | Bruce Chen | | 764 | 765 | -1 |
| 2004-09-20 | @ BOS | 148 | W 9-6 | 70-78 | 3 | 34,758 | Matt Riley | Tim Wakefield | Jason Grimsley | Tim Wakefield | Jorge Julio | 773 | 771 | 2 |
| 2004-09-21 | @ BOS | 149 | L 2-3 | 70-79 | 3 | 35,083 | Rodrigo Lopez | Curt Schilling | Keith Foulke | B.J. Ryan | | 775 | 774 | 1 |
| 2004-09-22 | @ BOS | 150 | L 6-7 | 70-80 | 3 | 35,103 | Sidney Ponson | Bronson Arroyo | Curt Leskanic | Rick Bauer | | 781 | 781 | 0 |
| 2004-09-23 | @ BOS | 151 | W 9-7 | 71-80 | 3 | 35,026 | Daniel Cabrera | Derek Lowe | Todd Williams | Ramiro Mendoza | | 790 | 788 | 2 |
| 2004-09-24 | vs DET | 152 | W 7-5 | 72-80 | 3 | 25,846 | Bruce Chen | Jason Johnson | John Parrish | Esteban Yan | | 797 | 793 | 4 |
| 2004-09-25 | vs DET | 153 | W 3-0 | 73-80 | 3 | 29,598 | Matt Riley | Jeremy Bonderman | Matt Riley | Jeremy Bonderman | B.J. Ryan | 800 | 793 | 7 |
| 2004-09-26 | vs DET | 154 | W 5-0 | 74-80 | 3 | 41,178 | Rodrigo Lopez | Mike Maroth | Rodrigo Lopez | Mike Maroth | | 805 | 793 | 12 |
| 2004-09-27 | vs TOR | 155 | L 1-4 | 74-81 | 3 | 17,809 | Sidney Ponson | Roy Halladay | Brandon League | Sidney Ponson | Miguel Batista | 806 | 797 | 9 |
| 2004-09-29 | vs TOR | 156 | W 7-6 | 76-81 | 3 | 0 | Bruce Chen | Ted Lilly | B.J. Ryan | Justin Speier | | 813 | 803 | 10 |
| 2004-09-29 | vs TOR | 157 | W 4-0 | 76-81 | 3 | 20,600 | Rick Bauer | Gustavo Chacin | Rick Bauer | Gustavo Chacin | | 817 | 803 | 14 |
| 2004-09-30 | vs TOR | 158 | W 9-3 | 77-81 | 3 | 18,793 | Matt Riley | Josh Towers | Matt Riley | Josh Towers | | 826 | 806 | 20 |
| 2004-10-01 | vs BOS | 159 | L 3-8 | 77-82 | 3 | 39,086 | Rodrigo Lopez | Tim Wakefield | Tim Wakefield | Rodrigo Lopez | | 829 | 814 | 15 |
| 2004-10-02 | vs BOS | 160 | L 5-7 | 77-84 | 3 | 48,540 | Daniel Cabrera | Bronson Arroyo | Terry Adams | Daniel Cabrera | Keith Foulke | 834 | 821 | 13 |
| 2004-10-02 | vs BOS | 161 | L 5-7 | 77-84 | 3 | 47,320 | Sidney Ponson | Pedro Astacio | Byung-Hyun Kim | Jason Grimsley | Curt Leskanic | 839 | 828 | 11 |
| 2004-10-03 | vs BOS | 162 | W 3-2 | 78-84 | 3 | 42,104 | Rick Bauer | Derek Lowe | Bruce Chen | Scott Williamson | B.J. Ryan | 842 | 830 | 12 |