| 2004-04-05 | vs PHI | 1 | W 2-1 | 1-0 | 3 | 35,702 | Kip Wells | Kevin Millwood | Kip Wells | Kevin Millwood | Jose Mesa | 2 | 1 | 1 |
| 2004-04-07 | vs PHI | 2 | L 4-5 | 1-1 | 4 | 15,126 | Kris Benson | Randy Wolf | Rheal Cormier | Brian Boehringer | Billy Wagner | 6 | 6 | 0 |
| 2004-04-08 | vs PHI | 3 | W 6-2 | 2-1 | 3 | 9,689 | Ryan Vogelsong | Vicente Padilla | Ryan Vogelsong | Vicente Padilla | Jose Mesa | 12 | 8 | 4 |
| 2004-04-09 | @ CIN | 4 | L 1-5 | 2-2 | 5 | 27,713 | Josh Fogg | Aaron Harang | Aaron Harang | Josh Fogg | | 13 | 13 | 0 |
| 2004-04-10 | @ CIN | 5 | L 1-3 | 2-3 | 6 | 23,449 | Kip Wells | Cory Lidle | Cory Lidle | Kip Wells | Danny Graves | 14 | 16 | -2 |
| 2004-04-11 | @ CIN | 6 | W 4-3 | 3-3 | 6 | 16,925 | Oliver Perez | Jimmy Haynes | Oliver Perez | Jimmy Haynes | Jose Mesa | 18 | 19 | -1 |
| 2004-04-12 | @ CHN | 7 | W 13-2 | 4-3 | 3 | 40,483 | Kris Benson | Greg Maddux | Kris Benson | Greg Maddux | Brian Meadows | 31 | 21 | 10 |
| 2004-04-14 | @ CHN | 8 | L 3-8 | 4-4 | 5 | 38,968 | Ryan Vogelsong | Matt Clement | Matt Clement | Ryan Vogelsong | | 34 | 29 | 5 |
| 2004-04-15 | @ CHN | 9 | L 5-10 | 4-5 | 5 | 39,450 | Josh Fogg | Carlos Zambrano | Carlos Zambrano | Josh Fogg | | 39 | 39 | 0 |
| 2004-04-16 | @ NYN | 10 | W 7-6 | 5-5 | 5 | 18,554 | Kip Wells | Tom Glavine | Kip Wells | Orber Moreno | Jose Mesa | 46 | 45 | 1 |
| 2004-04-17 | @ NYN | 11 | W 2-1 | 6-5 | 4 | 40,172 | Oliver Perez | Steve Trachsel | Brian Meadows | Steve Trachsel | Jose Mesa | 48 | 46 | 2 |
| 2004-04-18 | @ NYN | 12 | W 8-1 | 7-5 | 3 | 44,345 | Kris Benson | Jae Weong Seo | Kris Benson | Jae Weong Seo | | 56 | 47 | 9 |
| 2004-04-20 | vs CHN | 13 | L 1-9 | 7-6 | 4 | 11,746 | Ryan Vogelsong | Carlos Zambrano | Carlos Zambrano | Ryan Vogelsong | | 57 | 56 | 1 |
| 2004-04-21 | vs CHN | 14 | L 1-12 | 7-7 | 6 | 9,933 | Josh Fogg | Sergio Mitre | Sergio Mitre | Josh Fogg | | 58 | 68 | -10 |
| 2004-04-23 | vs CIN | 15 | L 4-6 | 7-8 | 6 | 17,350 | Kip Wells | Paul Wilson | Paul Wilson | Kip Wells | Danny Graves | 62 | 74 | -12 |
| 2004-04-24 | vs CIN | 16 | L 7-9 | 7-9 | 6 | 24,732 | Kris Benson | Jimmy Haynes | Todd Van Poppel | Kris Benson | Danny Graves | 69 | 83 | -14 |
| 2004-04-25 | vs CIN | 17 | W 6-0 | 8-9 | 6 | 13,264 | Oliver Perez | Jose Acevedo | Oliver Perez | Jose Acevedo | | 75 | 83 | -8 |
| 2004-04-26 | vs CIN | 18 | L 2-5 | 8-10 | 6 | 8,579 | Ryan Vogelsong | Aaron Harang | Aaron Harang | Ryan Vogelsong | Danny Graves | 77 | 88 | -11 |
| 2004-04-28 | vs HOU | 19 | W 4-2 | 9-10 | 6 | 9,813 | Josh Fogg | Roy Oswalt | Salomon Torres | Roy Oswalt | Jose Mesa | 81 | 90 | -9 |
| 2004-04-29 | vs HOU | 20 | L 0-2 | 9-11 | 6 | 19,485 | Kip Wells | Andy Pettitte | Andy Pettitte | Kip Wells | Octavio Dotel | 81 | 92 | -11 |
| 2004-04-30 | @ MIL | 21 | W 4-2 | 10-11 | 6 | 17,533 | Kris Benson | Ben Sheets | Kris Benson | Ben Sheets | Jose Mesa | 85 | 94 | -9 |
| 2004-05-01 | @ MIL | 22 | W 8-7 | 11-11 | 5 | 25,134 | Oliver Perez | Wes Obermueller | Jason Boyd | Luis Vizcaino | Jose Mesa | 93 | 101 | -8 |
| 2004-05-02 | @ MIL | 23 | W 4-3 | 12-11 | 3 | 16,392 | Ryan Vogelsong | Doug Davis | Brian Meadows | Jeff Bennett | Jose Mesa | 97 | 104 | -7 |
| 2004-05-04 | @ HOU | 24 | L 3-4 | 12-12 | 6 | 31,083 | Josh Fogg | Andy Pettitte | Andy Pettitte | Josh Fogg | Brad Lidge | 100 | 108 | -8 |
| 2004-05-05 | @ HOU | 25 | L 2-6 | 12-13 | 6 | 35,883 | Kip Wells | Roger Clemens | Roger Clemens | Kip Wells | | 102 | 114 | -12 |
| 2004-05-06 | @ HOU | 26 | L 2-5 | 12-14 | 6 | 36,055 | Kris Benson | Wade Miller | Wade Miller | Kris Benson | | 104 | 119 | -15 |
| 2004-05-07 | vs LAN | 27 | L 0-4 | 12-15 | 6 | 20,944 | Oliver Perez | Wilson Alvarez | Wilson Alvarez | Oliver Perez | | 104 | 123 | -19 |
| 2004-05-08 | vs LAN | 28 | L 3-4 | 12-16 | 6 | 26,610 | Ryan Vogelsong | Hideo Nomo | Guillermo Mota | Salomon Torres | Eric Gagne | 107 | 127 | -20 |
| 2004-05-09 | vs LAN | 29 | L 7-9 | 12-17 | 6 | 16,554 | Josh Fogg | Odalis Perez | Brian Falkenborg | John Grabow | | 114 | 136 | -22 |
| 2004-05-11 | @ COL | 30 | W 15-10 | 13-17 | 6 | 21,123 | Kip Wells | Scott Elarton | Salomon Torres | Javier Lopez | | 129 | 146 | -17 |
| 2004-05-13 | @ COL | 31 | L 5-7 | 14-18 | 6 | 0 | Kris Benson | Shawn Estes | Shawn Estes | Kris Benson | Shawn Chacon | 134 | 153 | -19 |
| 2004-05-13 | @ COL | 32 | W 11-2 | 14-18 | 6 | 20,041 | Oliver Perez | Jason Jennings | Oliver Perez | Jason Jennings | | 145 | 155 | -10 |
| 2004-05-14 | @ SFN | 33 | W 4-2 | 15-18 | 6 | 39,955 | Ryan Vogelsong | Dustin Hermanson | Brian Boehringer | Felix Rodriguez | Jose Mesa | 149 | 157 | -8 |
| 2004-05-15 | @ SFN | 34 | W 6-4 | 16-18 | 6 | 41,042 | Josh Fogg | Brett Tomko | Josh Fogg | Brett Tomko | Jose Mesa | 155 | 161 | -6 |
| 2004-05-16 | @ SFN | 35 | W 8-1 | 17-18 | 6 | 40,705 | Kip Wells | Jerome Williams | Kip Wells | Jerome Williams | | 163 | 162 | 1 |
| 2004-05-19 | vs SDN | 36 | L 3-6 | 17-20 | 6 | 0 | Kris Benson | Brian Lawrence | Brian Lawrence | Mike Johnston | Trevor Hoffman | 166 | 168 | -2 |
| 2004-05-19 | vs SDN | 37 | L 3-7 | 17-20 | 6 | 13,366 | Oliver Perez | Jake Peavy | Jake Peavy | Oliver Perez | | 169 | 175 | -6 |
| 2004-05-20 | vs SDN | 38 | W 9-7 | 18-20 | 6 | 11,029 | Ryan Vogelsong | Ismael Valdez | Mike Gonzalez | Brandon Puffer | Jose Mesa | 178 | 182 | -4 |
| 2004-05-22 | vs MIL | 39 | W 3-1 | 19-20 | 6 | 25,736 | Josh Fogg | Ben Sheets | Josh Fogg | Ben Sheets | Jose Mesa | 181 | 183 | -2 |
| 2004-05-23 | vs MIL | 40 | L 1-2 | 19-21 | 6 | 19,326 | Kip Wells | Doug Davis | Luis Vizcaino | Brian Meadows | Danny Kolb | 182 | 185 | -3 |
| 2004-05-26 | @ SLN | 41 | W 11-8 | 20-21 | 6 | 29,526 | Kris Benson | Jason Marquis | Kris Benson | Jason Marquis | | 193 | 193 | 0 |
| 2004-05-27 | @ SLN | 42 | L 3-6 | 20-22 | 6 | 31,107 | Ryan Vogelsong | Jeff Suppan | Jeff Suppan | Ryan Vogelsong | Jason Isringhausen | 196 | 199 | -3 |
| 2004-05-28 | vs CHN | 43 | W 9-5 | 22-22 | 6 | 0 | Kip Wells | Matt Clement | Salomon Torres | Joe Borowski | | 205 | 204 | 1 |
| 2004-05-28 | vs CHN | 44 | W 5-4 | 22-22 | 6 | 24,657 | Oliver Perez | Glendon Rusch | Mike Gonzalez | Francis Beltran | | 210 | 208 | 2 |
| 2004-05-29 | vs CHN | 45 | W 10-7 | 23-22 | 6 | 37,806 | Josh Fogg | Sergio Mitre | Josh Fogg | Sergio Mitre | | 220 | 215 | 5 |
| 2004-05-30 | vs CHN | 46 | L 1-12 | 23-23 | 6 | 30,392 | Sean Burnett | Carlos Zambrano | Carlos Zambrano | John Grabow | | 221 | 227 | -6 |
| 2004-05-31 | vs SLN | 47 | L 3-8 | 23-24 | 6 | 12,582 | Kris Benson | Jason Marquis | Jason Marquis | Kris Benson | | 224 | 235 | -11 |
| 2004-06-01 | vs SLN | 48 | L 1-8 | 23-25 | 6 | 11,540 | Ryan Vogelsong | Jeff Suppan | Jeff Suppan | Ryan Vogelsong | | 225 | 243 | -18 |
| 2004-06-02 | vs SLN | 49 | L 3-5 | 23-26 | 6 | 12,100 | Kip Wells | Chris Carpenter | Chris Carpenter | Mike Johnston | Jason Isringhausen | 228 | 248 | -20 |
| 2004-06-03 | vs SLN | 50 | L 2-4 | 23-27 | 6 | 15,386 | Oliver Perez | Woody Williams | Woody Williams | Oliver Perez | Jason Isringhausen | 230 | 252 | -22 |
| 2004-06-04 | @ CHN | 51 | W 2-1 | 24-27 | 6 | 40,024 | Josh Fogg | Mark Prior | Salomon Torres | Joe Borowski | Jose Mesa | 232 | 253 | -21 |
| 2004-06-05 | @ CHN | 52 | L 1-6 | 24-28 | 6 | 39,387 | Kris Benson | Carlos Zambrano | Carlos Zambrano | Kris Benson | | 233 | 259 | -26 |
| 2004-06-06 | @ CHN | 53 | L 1-4 | 24-29 | 6 | 39,016 | Ryan Vogelsong | Greg Maddux | Greg Maddux | Ryan Vogelsong | LaTroy Hawkins | 234 | 263 | -29 |
| 2004-06-07 | @ TEX | 54 | L 5-6 | 24-30 | 6 | 25,286 | Kip Wells | R.A. Dickey | Francisco Cordero | Mike Johnston | | 239 | 269 | -30 |
| 2004-06-10 | @ TEX | 55 | L 7-9 | 24-32 | 6 | 0 | Oliver Perez | Joaquin Benoit | Frank Francisco | Brian Meadows | Francisco Cordero | 246 | 278 | -32 |
| 2004-06-10 | @ TEX | 56 | L 4-10 | 24-32 | 6 | 27,219 | Josh Fogg | Kenny Rogers | Kenny Rogers | Josh Fogg | | 250 | 288 | -38 |
| 2004-06-11 | @ OAK | 57 | L 1-6 | 24-33 | 6 | 23,435 | Kris Benson | Tim Hudson | Tim Hudson | Kris Benson | | 251 | 294 | -43 |
| 2004-06-12 | @ OAK | 58 | L 11-12 | 24-34 | 6 | 24,606 | Ryan Vogelsong | Mark Redman | Arthur Rhodes | Mark Corey | | 262 | 306 | -44 |
| 2004-06-13 | @ OAK | 59 | L 3-13 | 24-35 | 6 | 34,328 | Kip Wells | Mark Mulder | Mark Mulder | Kip Wells | | 265 | 319 | -54 |
| 2004-06-15 | vs ANA | 60 | L 2-4 | 24-36 | 6 | 19,035 | Oliver Perez | Jarrod Washburn | Scot Shields | Salomon Torres | Francisco Rodriguez | 267 | 323 | -56 |
| 2004-06-16 | vs ANA | 61 | W 5-3 | 25-36 | 6 | 22,404 | Josh Fogg | John Lackey | Josh Fogg | John Lackey | Jose Mesa | 272 | 326 | -54 |
| 2004-06-17 | vs ANA | 62 | W 5-2 | 26-36 | 6 | 15,395 | Kris Benson | Bartolo Colon | Kris Benson | Bartolo Colon | Jose Mesa | 277 | 328 | -51 |
| 2004-06-18 | vs SEA | 63 | L 4-5 | 26-37 | 6 | 29,601 | Ryan Vogelsong | Jamie Moyer | Jamie Moyer | Ryan Vogelsong | Eddie Guardado | 281 | 333 | -52 |
| 2004-06-19 | vs SEA | 64 | L 1-5 | 26-38 | 6 | 24,341 | Sean Burnett | Joel Pineiro | Joel Pineiro | Sean Burnett | | 282 | 338 | -56 |
| 2004-06-20 | vs SEA | 65 | L 4-5 | 26-39 | 6 | 30,217 | Oliver Perez | Freddy Garcia | Freddy Garcia | Oliver Perez | Eddie Guardado | 286 | 343 | -57 |
| 2004-06-21 | @ HOU | 66 | L 5-7 | 26-40 | 6 | 33,443 | Josh Fogg | Tim Redding | Kirk Bullinger | Josh Fogg | Octavio Dotel | 291 | 350 | -59 |
| 2004-06-22 | @ HOU | 67 | L 4-5 | 26-41 | 6 | 31,819 | Kris Benson | Roy Oswalt | Roy Oswalt | Kris Benson | Brad Lidge | 295 | 355 | -60 |
| 2004-06-23 | @ HOU | 68 | W 7-2 | 27-41 | 6 | 34,242 | Ryan Vogelsong | Peter Munro | Ryan Vogelsong | Peter Munro | | 302 | 357 | -55 |
| 2004-06-24 | @ HOU | 69 | L 2-3 | 27-42 | 6 | 39,851 | Sean Burnett | Roger Clemens | Roger Clemens | Sean Burnett | Brad Lidge | 304 | 360 | -56 |
| 2004-06-25 | @ CIN | 70 | L 4-6 | 27-43 | 6 | 41,959 | Kip Wells | Jose Acevedo | Jose Acevedo | Salomon Torres | Danny Graves | 308 | 366 | -58 |
| 2004-06-26 | @ CIN | 71 | W 1-0 | 28-43 | 6 | 41,376 | Oliver Perez | Aaron Harang | Mark Corey | Todd Jones | Jose Mesa | 309 | 366 | -57 |
| 2004-06-27 | @ CIN | 72 | W 14-4 | 29-43 | 6 | 35,262 | Josh Fogg | Paul Wilson | Josh Fogg | Paul Wilson | | 323 | 370 | -47 |
| 2004-06-28 | vs SLN | 73 | W 2-1 | 30-43 | 6 | 15,544 | Kris Benson | Jeff Suppan | Jose Mesa | Julian Tavarez | | 325 | 371 | -46 |
| 2004-06-29 | vs SLN | 74 | W 3-0 | 31-43 | 6 | 18,152 | Sean Burnett | Chris Carpenter | Sean Burnett | Chris Carpenter | Jose Mesa | 328 | 371 | -43 |
| 2004-06-30 | vs SLN | 75 | W 6-5 | 32-43 | 6 | 22,368 | Kip Wells | Matt Morris | Jose Mesa | Julian Tavarez | | 334 | 376 | -42 |
| 2004-07-02 | vs MIL | 76 | W 8-1 | 34-43 | 6 | 0 | Oliver Perez | Doug Davis | Oliver Perez | Doug Davis | | 342 | 377 | -35 |
| 2004-07-02 | vs MIL | 77 | W 13-2 | 34-43 | 6 | 30,047 | Josh Fogg | Matt Wise | Josh Fogg | Matt Wise | | 355 | 379 | -24 |
| 2004-07-03 | vs MIL | 78 | W 5-3 | 35-43 | 6 | 28,443 | Kris Benson | Wes Obermueller | Kris Benson | Wes Obermueller | Jose Mesa | 360 | 382 | -22 |
| 2004-07-04 | vs MIL | 79 | W 6-2 | 36-43 | 6 | 19,029 | Sean Burnett | Chris Capuano | Sean Burnett | Chris Capuano | Jose Mesa | 366 | 384 | -18 |
| 2004-07-05 | @ FLO | 80 | W 3-1 | 37-43 | 6 | 13,224 | Kip Wells | Josh Beckett | Kip Wells | Josh Beckett | Jose Mesa | 369 | 385 | -16 |
| 2004-07-06 | @ FLO | 81 | L 3-6 | 37-44 | 6 | 12,330 | Josh Fogg | Dontrelle Willis | Nate Bump | Mark Corey | Armando Benitez | 372 | 391 | -19 |
| 2004-07-07 | @ FLO | 82 | W 4-3 | 38-44 | 6 | 15,135 | Oliver Perez | Carl Pavano | Oliver Perez | Carl Pavano | Jose Mesa | 376 | 394 | -18 |
| 2004-07-08 | @ MON | 83 | L 1-2 | 38-45 | 6 | 7,746 | Kris Benson | Tony Armas | Luis Ayala | John Grabow | Chad Cordero | 377 | 396 | -19 |
| 2004-07-09 | @ MON | 84 | W 11-0 | 39-45 | 6 | 7,436 | Sean Burnett | Shawn Hill | Sean Burnett | Shawn Hill | | 388 | 396 | -8 |
| 2004-07-10 | @ MON | 85 | L 0-4 | 39-46 | 6 | 8,780 | Kip Wells | Rocky Biddle | Rocky Biddle | Kip Wells | | 388 | 400 | -12 |
| 2004-07-11 | @ MON | 86 | L 1-2 | 39-47 | 6 | 8,101 | Josh Fogg | Scott Downs | Scott Downs | Josh Fogg | Chad Cordero | 389 | 402 | -13 |
| 2004-07-16 | vs FLO | 87 | W 6-2 | 40-47 | 6 | 28,563 | Kris Benson | A.J. Burnett | Kris Benson | A.J. Burnett | Jose Mesa | 395 | 404 | -9 |
| 2004-07-17 | vs FLO | 88 | W 4-2 | 41-47 | 6 | 26,729 | Kip Wells | Carl Pavano | Salomon Torres | Armando Benitez | Jose Mesa | 399 | 406 | -7 |
| 2004-07-18 | vs FLO | 89 | W 4-2 | 42-47 | 6 | 18,048 | Oliver Perez | Brad Penny | Salomon Torres | Billy Koch | Jose Mesa | 403 | 408 | -5 |
| 2004-07-19 | vs MON | 90 | L 2-6 | 42-48 | 6 | 14,787 | Josh Fogg | Rocky Biddle | Joe Horgan | John Grabow | | 405 | 414 | -9 |
| 2004-07-20 | vs MON | 91 | W 2-1 | 43-48 | 6 | 18,075 | Sean Burnett | Livan Hernandez | Sean Burnett | Livan Hernandez | Jose Mesa | 407 | 415 | -8 |
| 2004-07-21 | @ ATL | 92 | W 4-3 | 44-48 | 6 | 30,131 | Kris Benson | Paul Byrd | Kris Benson | Paul Byrd | Jose Mesa | 411 | 418 | -7 |
| 2004-07-22 | @ ATL | 93 | L 1-2 | 44-49 | 6 | 32,963 | Kip Wells | Russ Ortiz | Chris Reitsma | Salomon Torres | | 412 | 420 | -8 |
| 2004-07-23 | vs CIN | 94 | W 6-3 | 45-49 | 6 | 37,703 | Oliver Perez | Jose Acevedo | Oliver Perez | Jose Acevedo | Jose Mesa | 418 | 423 | -5 |
| 2004-07-24 | vs CIN | 95 | W 14-4 | 46-49 | 6 | 37,752 | Josh Fogg | Aaron Harang | John Grabow | Aaron Harang | | 432 | 427 | 5 |
| 2004-07-25 | vs CIN | 96 | W 6-5 | 47-49 | 6 | 24,962 | Sean Burnett | Brandon Claussen | Sean Burnett | Todd Van Poppel | Jose Mesa | 438 | 432 | 6 |
| 2004-07-26 | vs ATL | 97 | L 2-4 | 47-50 | 6 | 19,164 | Kris Benson | Jaret Wright | Jaret Wright | Kris Benson | John Smoltz | 440 | 436 | 4 |
| 2004-07-27 | vs ATL | 98 | W 8-4 | 48-50 | 5 | 15,946 | Kip Wells | Paul Byrd | Mike Gonzalez | Kevin Gryboski | | 448 | 440 | 8 |
| 2004-07-28 | vs ATL | 99 | L 0-1 | 48-51 | 6 | 22,977 | Oliver Perez | Russ Ortiz | Russ Ortiz | Oliver Perez | John Smoltz | 448 | 441 | 7 |
| 2004-07-29 | vs ATL | 100 | L 2-3 | 48-52 | 6 | 25,988 | Josh Fogg | John Thomson | Juan Cruz | Jose Mesa | John Smoltz | 450 | 444 | 6 |
| 2004-07-30 | @ MIL | 101 | L 0-5 | 48-53 | 6 | 34,702 | Sean Burnett | Doug Davis | Doug Davis | Sean Burnett | | 450 | 449 | 1 |
| 2004-07-31 | @ MIL | 102 | W 4-1 | 49-53 | 6 | 35,152 | Ryan Vogelsong | Victor Santos | Ryan Vogelsong | Victor Santos | Jose Mesa | 454 | 450 | 4 |
| 2004-08-01 | @ MIL | 103 | L 7-8 | 49-54 | 6 | 25,047 | Kip Wells | Ben Sheets | Luis Vizcaino | Brian Meadows | | 461 | 458 | 3 |
| 2004-08-03 | @ LAN | 104 | L 2-3 | 49-55 | 6 | 34,581 | Oliver Perez | Brad Penny | Brad Penny | Oliver Perez | Eric Gagne | 463 | 461 | 2 |
| 2004-08-04 | @ LAN | 105 | L 1-2 | 49-56 | 6 | 34,792 | Josh Fogg | Jose Lima | Jose Lima | Josh Fogg | Eric Gagne | 464 | 463 | 1 |
| 2004-08-05 | @ LAN | 106 | L 3-8 | 49-57 | 6 | 38,852 | Sean Burnett | Jeff Weaver | Jeff Weaver | Sean Burnett | | 467 | 471 | -4 |
| 2004-08-06 | @ SDN | 107 | L 1-13 | 49-58 | 6 | 40,026 | Ryan Vogelsong | Jake Peavy | Jake Peavy | Ryan Vogelsong | | 468 | 484 | -16 |
| 2004-08-07 | @ SDN | 108 | W 3-1 | 50-58 | 6 | 40,681 | Kip Wells | David Wells | Kip Wells | David Wells | Jose Mesa | 471 | 485 | -14 |
| 2004-08-08 | @ SDN | 109 | W 4-2 | 51-58 | 6 | 39,742 | Oliver Perez | Brian Lawrence | Oliver Perez | Brian Lawrence | Jose Mesa | 475 | 487 | -12 |
| 2004-08-10 | vs SFN | 110 | W 8-7 | 52-58 | 6 | 24,930 | Josh Fogg | Brett Tomko | Jose Mesa | Matt Herges | | 483 | 494 | -11 |
| 2004-08-11 | vs SFN | 111 | W 8-6 | 53-58 | 5 | 25,814 | Sean Burnett | Kirk Rueter | John Grabow | Dustin Hermanson | | 491 | 500 | -9 |
| 2004-08-12 | vs SFN | 112 | L 0-7 | 53-59 | 5 | 24,446 | Ryan Vogelsong | Jason Schmidt | Jason Schmidt | Ryan Vogelsong | | 491 | 507 | -16 |
| 2004-08-13 | vs COL | 113 | L 3-9 | 53-60 | 6 | 27,522 | Kip Wells | Jeff Fassero | Jeff Fassero | Kip Wells | | 494 | 516 | -22 |
| 2004-08-14 | vs COL | 114 | W 6-1 | 54-60 | 5 | 37,312 | Oliver Perez | Jamey Wright | Oliver Perez | Jamey Wright | | 500 | 517 | -17 |
| 2004-08-15 | vs COL | 115 | W 3-0 | 55-60 | 5 | 24,862 | Josh Fogg | Joe Kennedy | Josh Fogg | Joe Kennedy | Jose Mesa | 503 | 517 | -14 |
| 2004-08-16 | @ ARI | 116 | W 8-7 | 56-60 | 4 | 28,768 | Sean Burnett | Brandon Webb | Jose Mesa | Greg Aquino | Mike Gonzalez | 511 | 524 | -13 |
| 2004-08-17 | @ ARI | 117 | W 7-1 | 57-60 | 4 | 30,030 | Ryan Vogelsong | Steve Randolph | Ryan Vogelsong | Steve Randolph | | 518 | 525 | -7 |
| 2004-08-18 | @ ARI | 118 | L 3-6 | 57-61 | 4 | 28,066 | John Van Benschoten | Casey Fossum | Casey Fossum | John Van Benschoten | Greg Aquino | 521 | 531 | -10 |
| 2004-08-19 | @ SLN | 119 | W 3-2 | 58-61 | 4 | 33,854 | Oliver Perez | Jason Marquis | Jose Mesa | Steve Kline | John Grabow | 524 | 533 | -9 |
| 2004-08-20 | @ SLN | 120 | L 4-5 | 58-63 | 5 | 32,062 | Josh Fogg | Dan Haren | Dan Haren | Josh Fogg | Jason Isringhausen | 528 | 538 | -10 |
| 2004-08-20 | @ SLN | 121 | L 3-5 | 58-63 | 5 | 38,640 | Nelson Figueroa | Chris Carpenter | Chris Carpenter | Mike Gonzalez | Jason Isringhausen | 531 | 543 | -12 |
| 2004-08-21 | @ SLN | 122 | L 6-10 | 58-64 | 5 | 46,017 | Sean Burnett | Jeff Suppan | Jeff Suppan | Sean Burnett | | 537 | 553 | -16 |
| 2004-08-22 | @ SLN | 123 | L 4-11 | 58-65 | 5 | 35,345 | Ryan Vogelsong | Matt Morris | Matt Morris | Ryan Vogelsong | Steve Kline | 541 | 564 | -23 |
| 2004-08-23 | vs ARI | 124 | L 4-5 | 58-66 | 5 | 25,154 | John Van Benschoten | Casey Fossum | Shane Nance | John Grabow | Greg Aquino | 545 | 569 | -24 |
| 2004-08-24 | vs ARI | 125 | W 3-1 | 59-66 | 5 | 16,332 | Oliver Perez | Edgar Gonzalez | Oliver Perez | Edgar Gonzalez | Jose Mesa | 548 | 570 | -22 |
| 2004-08-25 | vs ARI | 126 | W 2-1 | 60-66 | 5 | 24,853 | Josh Fogg | Randy Johnson | Josh Fogg | Randy Johnson | Jose Mesa | 550 | 571 | -21 |
| 2004-08-27 | vs SLN | 127 | L 5-8 | 60-67 | 5 | 27,475 | Ryan Vogelsong | Jeff Suppan | Jeff Suppan | Ryan Vogelsong | Jason Isringhausen | 555 | 579 | -24 |
| 2004-08-28 | vs SLN | 128 | L 4-6 | 60-68 | 5 | 19,167 | Nelson Figueroa | Matt Morris | Matt Morris | Nelson Figueroa | Jason Isringhausen | 559 | 585 | -26 |
| 2004-08-29 | vs SLN | 129 | L 0-4 | 60-69 | 5 | 25,005 | Oliver Perez | Jason Marquis | Jason Marquis | Oliver Perez | Julian Tavarez | 559 | 589 | -30 |
| 2004-08-30 | @ MIL | 130 | W 5-1 | 61-69 | 5 | 23,512 | Josh Fogg | Ben Hendrickson | Josh Fogg | Ben Hendrickson | | 564 | 590 | -26 |
| 2004-08-31 | @ MIL | 131 | L 2-4 | 61-70 | 5 | 13,704 | John Van Benschoten | Doug Davis | Matt Wise | John Van Benschoten | Danny Kolb | 566 | 594 | -28 |
| 2004-09-01 | @ MIL | 132 | W 5-2 | 62-70 | 5 | 15,625 | Ryan Vogelsong | Victor Santos | Salomon Torres | Jeff Bennett | Jose Mesa | 571 | 596 | -25 |
| 2004-09-02 | @ MIL | 133 | L 1-7 | 62-71 | 5 | 11,763 | David Williams | Ben Sheets | Ben Sheets | David Williams | | 572 | 603 | -31 |
| 2004-09-03 | @ HOU | 134 | L 6-8 | 62-72 | 5 | 40,992 | Oliver Perez | Roger Clemens | Roger Clemens | Oliver Perez | Brad Lidge | 578 | 611 | -33 |
| 2004-09-04 | @ HOU | 135 | L 5-6 | 62-73 | 5 | 38,605 | Josh Fogg | Carlos Hernandez | Chad Qualls | Nelson Figueroa | Brad Lidge | 583 | 617 | -34 |
| 2004-09-05 | @ HOU | 136 | L 5-10 | 62-74 | 5 | 40,569 | Kip Wells | Peter Munro | Peter Munro | John Van Benschoten | | 588 | 627 | -39 |
| 2004-09-06 | vs MIL | 137 | L 5-9 | 62-75 | 5 | 12,771 | Ryan Vogelsong | Gary Glover | Gary Glover | Ryan Vogelsong | Danny Kolb | 593 | 636 | -43 |
| 2004-09-07 | vs MIL | 138 | W 2-0 | 63-75 | 5 | 20,563 | David Williams | Ben Sheets | David Williams | Ben Sheets | Jose Mesa | 595 | 636 | -41 |
| 2004-09-09 | vs HOU | 139 | W 3-1 | 64-76 | 4 | 0 | Oliver Perez | Carlos Hernandez | Oliver Perez | Carlos Hernandez | Jose Mesa | 598 | 637 | -39 |
| 2004-09-09 | vs HOU | 140 | L 2-9 | 64-76 | 4 | 10,495 | Josh Fogg | Tim Redding | Mike Gallo | Josh Fogg | | 600 | 646 | -46 |
| 2004-09-10 | vs HOU | 141 | W 6-1 | 65-76 | 4 | 26,097 | John Van Benschoten | Peter Munro | John Van Benschoten | Peter Munro | | 606 | 647 | -41 |
| 2004-09-11 | vs HOU | 142 | W 5-2 | 66-76 | 4 | 14,877 | Ryan Vogelsong | Brandon Backe | Ryan Vogelsong | Brandon Backe | Jose Mesa | 611 | 649 | -38 |
| 2004-09-12 | vs HOU | 143 | L 4-5 | 66-77 | 4 | 11,521 | David Williams | Roy Oswalt | Brad Lidge | Jose Mesa | Chad Qualls | 615 | 654 | -39 |
| 2004-09-13 | @ CHN | 144 | L 2-7 | 66-78 | 5 | 38,326 | Frank Brooks | Greg Maddux | Greg Maddux | Frank Brooks | | 617 | 661 | -44 |
| 2004-09-14 | @ CHN | 145 | L 2-3 | 66-79 | 5 | 38,676 | Josh Fogg | Matt Clement | Todd Wellemeyer | Brian Meadows | | 619 | 664 | -45 |
| 2004-09-15 | @ CHN | 146 | L 5-13 | 66-80 | 5 | 38,395 | Oliver Perez | Mark Prior | Michael Wuertz | Oliver Perez | Ryan Dempster | 624 | 677 | -53 |
| 2004-09-18 | vs NYN | 147 | L 7-8 | 66-81 | 5 | 19,236 | John Van Benschoten | Tom Glavine | Tyler Yates | Salomon Torres | Braden Looper | 631 | 685 | -54 |
| 2004-09-19 | vs NYN | 148 | W 1-0 | 68-81 | 5 | 0 | Ryan Vogelsong | Aaron Heilman | Ryan Vogelsong | Aaron Heilman | Jose Mesa | 632 | 685 | -53 |
| 2004-09-19 | vs NYN | 149 | W 6-1 | 68-81 | 5 | 18,219 | David Williams | Kris Benson | David Williams | Kris Benson | | 638 | 686 | -48 |
| 2004-09-21 | vs CHN | 150 | L 4-5 | 68-82 | 5 | 12,701 | Josh Fogg | Kerry Wood | LaTroy Hawkins | Salomon Torres | Ryan Dempster | 642 | 691 | -49 |
| 2004-09-22 | vs CHN | 151 | L 0-1 | 68-83 | 5 | 22,257 | Oliver Perez | Carlos Zambrano | Carlos Zambrano | Oliver Perez | Mike Remlinger | 642 | 692 | -50 |
| 2004-09-23 | vs CHN | 152 | L 3-6 | 68-84 | 5 | 13,298 | Nelson Figueroa | Greg Maddux | Greg Maddux | Nelson Figueroa | LaTroy Hawkins | 645 | 698 | -53 |
| 2004-09-24 | vs CIN | 153 | L 8-14 | 68-85 | 5 | 29,066 | Ryan Vogelsong | Aaron Harang | Aaron Harang | Ryan Vogelsong | | 653 | 712 | -59 |
| 2004-09-25 | vs CIN | 154 | L 4-7 | 68-86 | 5 | 26,500 | David Williams | Paul Wilson | Paul Wilson | David Williams | Joe Valentine | 657 | 719 | -62 |
| 2004-09-26 | vs CIN | 155 | W 4-2 | 69-86 | 5 | 23,841 | Josh Fogg | Jose Acevedo | Josh Fogg | Jose Acevedo | Jose Mesa | 661 | 721 | -60 |
| 2004-09-27 | @ PHI | 156 | W 6-1 | 70-86 | 5 | 30,268 | Oliver Perez | Eric Milton | Oliver Perez | Eric Milton | | 667 | 722 | -55 |
| 2004-09-29 | @ PHI | 157 | L 4-8 | 70-88 | 5 | 0 | Ian Snell | Vicente Padilla | Vicente Padilla | Ian Snell | | 671 | 730 | -59 |
| 2004-09-29 | @ PHI | 158 | L 3-8 | 70-88 | 5 | 33,127 | Ryan Vogelsong | Brett Myers | Brett Myers | Salomon Torres | | 674 | 738 | -64 |
| 2004-10-01 | @ CIN | 159 | L 1-5 | 70-89 | 5 | 26,841 | David Williams | Paul Wilson | Paul Wilson | David Williams | | 675 | 743 | -68 |
| 2004-10-02 | @ CIN | 160 | W 3-1 | 71-89 | 5 | 26,128 | Josh Fogg | Todd Van Poppel | Josh Fogg | Todd Van Poppel | Jose Mesa | 678 | 744 | -66 |
| 2004-10-03 | @ CIN | 161 | W 2-0 | 72-89 | 5 | 30,854 | Oliver Perez | Brandon Claussen | Oliver Perez | Brandon Claussen | Jose Mesa | 680 | 744 | -64 |