| 1998-03-31 | vs SDN | 1 | L 2-10 | 0-1 | 3 | 54,578 | Mike Remlinger | Kevin Brown | Kevin Brown | Mike Remlinger | | 2 | 10 | -8 |
| 1998-04-01 | vs SDN | 2 | L 9-10 | 0-2 | 5 | 13,706 | Pete Harnisch | Joey Hamilton | Joey Hamilton | Scott Sullivan | Trevor Hoffman | 11 | 20 | -9 |
| 1998-04-02 | vs SDN | 3 | W 5-1 | 1-2 | 5 | 13,630 | Steve Cooke | Andy Ashby | Steve Cooke | Andy Ashby | Jeff Shaw | 16 | 21 | -5 |
| 1998-04-03 | vs LAN | 4 | W 6-3 | 2-2 | 5 | 16,027 | David Weathers | Hideo Nomo | David Weathers | Darren Hall | Jeff Shaw | 22 | 24 | -2 |
| 1998-04-04 | vs LAN | 5 | W 3-1 | 3-2 | 4 | 20,464 | Brett Tomko | Ismael Valdez | Brett Tomko | Ismael Valdez | Jeff Shaw | 25 | 25 | 0 |
| 1998-04-05 | vs LAN | 6 | L 0-1 | 3-3 | 4 | 19,790 | Mike Remlinger | Ramon Martinez | Ramon Martinez | Mike Remlinger | Scott Radinsky | 25 | 26 | -1 |
| 1998-04-07 | @ SDN | 7 | L 2-3 | 3-4 | 5 | 55,454 | Pete Harnisch | Joey Hamilton | Trevor Hoffman | Jeff Shaw | | 27 | 29 | -2 |
| 1998-04-08 | @ SDN | 8 | L 3-6 | 3-5 | 6 | 19,626 | Gabe White | Andy Ashby | Andy Ashby | Gabe White | Trevor Hoffman | 30 | 35 | -5 |
| 1998-04-09 | @ SDN | 9 | L 2-6 | 3-6 | 6 | 24,482 | Brett Tomko | Mark Langston | Brian Boehringer | Brett Tomko | | 32 | 41 | -9 |
| 1998-04-10 | @ COL | 10 | W 18-7 | 4-6 | 6 | 48,013 | David Weathers | Darryl Kile | Ricardo Jordan | Darryl Kile | Scott Sullivan | 50 | 48 | 2 |
| 1998-04-11 | @ COL | 11 | W 12-5 | 5-6 | 6 | 48,053 | Mike Remlinger | John Thomson | Mike Remlinger | John Thomson | Stan Belinda | 62 | 53 | 9 |
| 1998-04-12 | @ COL | 12 | W 10-4 | 6-6 | 6 | 46,921 | Pete Harnisch | Pedro Astacio | Pete Harnisch | Pedro Astacio | | 72 | 57 | 15 |
| 1998-04-13 | @ COL | 13 | L 4-8 | 6-7 | 6 | 44,488 | Gabe White | Jamey Wright | Curt Leskanic | Stan Belinda | | 76 | 65 | 11 |
| 1998-04-15 | vs HOU | 14 | W 4-1 | 7-7 | 4 | 15,619 | Brett Tomko | Shane Reynolds | Brett Tomko | Shane Reynolds | Jeff Shaw | 80 | 66 | 14 |
| 1998-04-16 | vs HOU | 15 | L 4-7 | 7-8 | 5 | 14,596 | David Weathers | Mike Hampton | Mike Hampton | David Weathers | Billy Wagner | 84 | 73 | 11 |
| 1998-04-17 | vs NYN | 16 | W 4-3 | 8-8 | 5 | 21,384 | Mike Remlinger | Bobby Jones | Mike Remlinger | Bobby Jones | Jeff Shaw | 88 | 76 | 12 |
| 1998-04-18 | vs NYN | 17 | L 4-5 | 8-9 | 5 | 21,213 | Pete Harnisch | Masato Yoshii | Mel Rojas | Stan Belinda | John Franco | 92 | 81 | 11 |
| 1998-04-19 | vs NYN | 18 | L 0-14 | 8-10 | 5 | 16,743 | Gabe White | Al Leiter | Al Leiter | Gabe White | | 92 | 95 | -3 |
| 1998-04-21 | @ PHI | 19 | W 6-3 | 9-10 | 5 | 13,452 | Brett Tomko | Curt Schilling | Brett Tomko | Curt Schilling | Jeff Shaw | 98 | 98 | 0 |
| 1998-04-22 | @ PHI | 20 | L 4-5 | 9-11 | 5 | 11,102 | Mark Hutton | Tyler Green | Tyler Green | Gabe White | Ricky Bottalico | 102 | 103 | -1 |
| 1998-04-23 | @ PHI | 21 | L 3-6 | 9-12 | 5 | 10,445 | Pete Harnisch | Garrett Stephenson | Jerry Spradlin | Scott Sullivan | Mark Leiter | 105 | 109 | -4 |
| 1998-04-24 | @ NYN | 22 | L 2-3 | 9-13 | 6 | 15,546 | Mike Remlinger | Bobby Jones | Bobby Jones | Jeff Shaw | John Franco | 107 | 112 | -5 |
| 1998-04-25 | @ NYN | 23 | W 2-0 | 10-13 | 5 | 22,652 | David Weathers | Masato Yoshii | David Weathers | Masato Yoshii | Jeff Shaw | 109 | 112 | -3 |
| 1998-04-27 | vs PHI | 24 | W 3-1 | 11-13 | 5 | 13,889 | Brett Tomko | Tyler Green | Stan Belinda | Tyler Green | | 112 | 113 | -1 |
| 1998-04-28 | vs PHI | 25 | L 8-11 | 11-14 | 5 | 15,890 | Scott Winchester | Garrett Stephenson | Mark Leiter | Stan Belinda | Darrin Winston | 120 | 124 | -4 |
| 1998-04-29 | vs PHI | 26 | W 1-0 | 12-14 | 5 | 16,411 | Pete Harnisch | Mike Grace | Pete Harnisch | Mike Grace | | 121 | 124 | -3 |
| 1998-05-01 | @ MIL | 27 | L 2-5 | 12-15 | 5 | 11,030 | Mike Remlinger | Scott Karl | Scott Karl | Mike Remlinger | Doug Jones | 123 | 129 | -6 |
| 1998-05-02 | @ MIL | 28 | W 8-5 | 13-15 | 5 | 17,708 | David Weathers | Jeff Juden | Gabe White | Chad Fox | Jeff Shaw | 131 | 134 | -3 |
| 1998-05-03 | @ MIL | 29 | W 5-3 | 14-15 | 5 | 12,358 | Brett Tomko | Cal Eldred | Brett Tomko | Cal Eldred | Jeff Shaw | 136 | 137 | -1 |
| 1998-05-04 | @ MON | 30 | W 4-1 | 15-15 | 5 | 6,616 | Scott Winchester | Trey Moore | Scott Winchester | Trey Moore | Jeff Shaw | 140 | 138 | 2 |
| 1998-05-05 | @ MON | 31 | L 2-3 | 15-16 | 5 | 6,549 | Pete Harnisch | Miguel Batista | Ugueth Urbina | Stan Belinda | | 142 | 141 | 1 |
| 1998-05-06 | @ MON | 32 | W 4-2 | 16-16 | 5 | 7,261 | Mike Remlinger | Javier Vazquez | Mike Remlinger | Javier Vazquez | Jeff Shaw | 146 | 143 | 3 |
| 1998-05-07 | @ PIT | 33 | L 7-8 | 16-17 | 5 | 8,400 | David Weathers | Esteban Loaiza | Elmer Dessens | Stan Belinda | Rich Loiselle | 153 | 151 | 2 |
| 1998-05-08 | @ PIT | 34 | W 5-3 | 17-17 | 4 | 13,848 | Brett Tomko | Jon Lieber | Stan Belinda | Ricardo Rincon | Jeff Shaw | 158 | 154 | 4 |
| 1998-05-09 | @ PIT | 35 | L 1-6 | 17-18 | 5 | 27,185 | Scott Winchester | Jose Silva | Jose Silva | Scott Winchester | Chris Peters | 159 | 160 | -1 |
| 1998-05-10 | @ PIT | 36 | W 4-3 | 18-18 | 4 | 19,507 | Pete Harnisch | Francisco Cordova | Stan Belinda | Rich Loiselle | | 163 | 163 | 0 |
| 1998-05-11 | vs ATL | 37 | L 1-8 | 18-19 | 5 | 19,285 | Mike Remlinger | Greg Maddux | Greg Maddux | Mike Remlinger | | 164 | 171 | -7 |
| 1998-05-12 | vs ATL | 38 | L 1-5 | 18-20 | 5 | 19,033 | David Weathers | John Smoltz | John Smoltz | David Weathers | | 165 | 176 | -11 |
| 1998-05-13 | vs FLO | 39 | W 10-4 | 19-20 | 5 | 15,121 | Brett Tomko | Jesus Sanchez | Brett Tomko | Donn Pall | | 175 | 180 | -5 |
| 1998-05-14 | vs FLO | 40 | W 11-8 | 20-20 | 4 | 14,561 | Scott Winchester | Andy Larkin | Scott Winchester | Andy Larkin | Jeff Shaw | 186 | 188 | -2 |
| 1998-05-15 | vs CHN | 41 | W 11-3 | 21-20 | 4 | 21,408 | Pete Harnisch | Geremi Gonzalez | Pete Harnisch | Geremi Gonzalez | | 197 | 191 | 6 |
| 1998-05-16 | vs CHN | 42 | L 4-5 | 21-21 | 4 | 30,505 | Mike Remlinger | Mark Clark | Mark Clark | Mike Remlinger | Rod Beck | 201 | 196 | 5 |
| 1998-05-17 | vs CHN | 43 | L 1-10 | 21-22 | 5 | 33,480 | David Weathers | Kerry Wood | Kerry Wood | David Weathers | Terry Mulholland | 202 | 206 | -4 |
| 1998-05-19 | @ NYN | 44 | L 3-7 | 21-24 | 5 | 0 | Brett Tomko | Bobby Jones | Bobby Jones | Brett Tomko | | 205 | 213 | -8 |
| 1998-05-19 | @ NYN | 45 | L 3-5 | 21-24 | 5 | 15,558 | Scott Winchester | Brian Bohanon | Brian Bohanon | Scott Winchester | John Franco | 208 | 218 | -10 |
| 1998-05-20 | @ NYN | 46 | W 8-6 | 22-24 | 5 | 12,834 | Pete Harnisch | Dave Mlicki | Pete Harnisch | John Hudek | Jeff Shaw | 216 | 224 | -8 |
| 1998-05-21 | @ NYN | 47 | L 1-6 | 22-25 | 6 | 13,766 | Mark Hutton | Masato Yoshii | Masato Yoshii | Mark Hutton | | 217 | 230 | -13 |
| 1998-05-22 | vs COL | 48 | L 2-3 | 22-26 | 6 | 21,410 | David Weathers | Jamey Wright | Jamey Wright | David Weathers | Jerry DiPoto | 219 | 233 | -14 |
| 1998-05-23 | vs COL | 49 | W 4-1 | 23-26 | 6 | 20,034 | Scott Winchester | Pedro Astacio | Scott Winchester | Pedro Astacio | | 223 | 234 | -11 |
| 1998-05-24 | vs COL | 50 | L 1-3 | 23-27 | 6 | 21,298 | Brett Tomko | Bobby Jones | Bobby Jones | Brett Tomko | Jerry DiPoto | 224 | 237 | -13 |
| 1998-05-25 | vs SFN | 51 | L 1-3 | 23-28 | 6 | 17,980 | Pete Harnisch | Orel Hershiser | Orel Hershiser | Pete Harnisch | Robb Nen | 225 | 240 | -15 |
| 1998-05-26 | vs SFN | 52 | L 2-5 | 23-29 | 6 | 16,096 | Mike Remlinger | Kirk Rueter | Kirk Rueter | Mike Remlinger | Robb Nen | 227 | 245 | -18 |
| 1998-05-27 | vs SFN | 53 | W 7-5 | 24-29 | 5 | 17,742 | Eddie Priest | Mark Gardner | Scott Sullivan | Jim Poole | Jeff Shaw | 234 | 250 | -16 |
| 1998-05-28 | @ LAN | 54 | L 3-4 | 24-30 | 6 | 37,273 | Scott Winchester | Ramon Martinez | Jim Bruske | Stan Belinda | | 237 | 254 | -17 |
| 1998-05-29 | @ LAN | 55 | W 8-4 | 25-30 | 5 | 41,479 | Brett Tomko | Chan Ho Park | Jeff Shaw | Dennys Reyes | | 245 | 258 | -13 |
| 1998-05-30 | @ LAN | 56 | W 7-3 | 26-30 | 5 | 37,643 | Pete Harnisch | Hideo Nomo | Pete Harnisch | Hideo Nomo | | 252 | 261 | -9 |
| 1998-05-31 | @ LAN | 57 | W 6-5 | 27-30 | 5 | 41,306 | Mike Remlinger | Ismael Valdez | Danny Graves | Scott Radinsky | Jeff Shaw | 258 | 266 | -8 |
| 1998-06-01 | @ SFN | 58 | L 3-16 | 27-31 | 6 | 10,986 | Eddie Priest | Mark Gardner | Mark Gardner | Eddie Priest | | 261 | 282 | -21 |
| 1998-06-02 | @ SFN | 59 | L 2-4 | 27-32 | 6 | 10,320 | Scott Winchester | Danny Darwin | Danny Darwin | Scott Winchester | Robb Nen | 263 | 286 | -23 |
| 1998-06-03 | @ SFN | 60 | L 5-8 | 27-33 | 6 | 13,524 | Brett Tomko | Shawn Estes | Shawn Estes | Brett Tomko | Robb Nen | 268 | 294 | -26 |
| 1998-06-05 | vs CLE | 61 | W 2-1 | 28-33 | 6 | 43,532 | Pete Harnisch | Charles Nagy | Pete Harnisch | Charles Nagy | Jeff Shaw | 270 | 295 | -25 |
| 1998-06-06 | vs CLE | 62 | L 1-10 | 28-34 | 6 | 51,796 | Mike Remlinger | Jaret Wright | Jaret Wright | Mike Remlinger | | 271 | 305 | -34 |
| 1998-06-07 | vs CLE | 63 | L 1-6 | 28-35 | 6 | 49,589 | Scott Klingenbeck | Dave Burba | Dave Burba | Scott Klingenbeck | | 272 | 311 | -39 |
| 1998-06-08 | @ SDN | 64 | L 2-4 | 28-36 | 6 | 14,620 | Scott Winchester | Joey Hamilton | Joey Hamilton | Scott Sullivan | Trevor Hoffman | 274 | 315 | -41 |
| 1998-06-09 | @ SDN | 65 | L 1-5 | 28-37 | 6 | 14,857 | Brett Tomko | Andy Ashby | Andy Ashby | Brett Tomko | Trevor Hoffman | 275 | 320 | -45 |
| 1998-06-10 | @ SDN | 66 | L 1-2 | 28-38 | 6 | 12,957 | Pete Harnisch | Kevin Brown | Kevin Brown | Jeff Shaw | | 276 | 322 | -46 |
| 1998-06-12 | vs HOU | 67 | W 8-1 | 29-38 | 6 | 21,310 | Mike Remlinger | Jose Lima | Mike Remlinger | Jose Lima | | 284 | 323 | -39 |
| 1998-06-13 | vs HOU | 68 | W 7-4 | 30-38 | 6 | 28,055 | Scott Klingenbeck | Shane Reynolds | Scott Klingenbeck | Shane Reynolds | Jeff Shaw | 291 | 327 | -36 |
| 1998-06-14 | vs HOU | 69 | L 3-6 | 30-39 | 6 | 22,008 | Scott Winchester | Sean Bergman | Billy Wagner | Jeff Shaw | | 294 | 333 | -39 |
| 1998-06-15 | vs HOU | 70 | L 2-13 | 30-40 | 6 | 14,556 | Brett Tomko | Mike Hampton | Mike Magnante | Brett Tomko | | 296 | 346 | -50 |
| 1998-06-16 | vs ARI | 71 | L 1-5 | 30-41 | 6 | 15,975 | Pete Harnisch | Omar Daal | Omar Daal | Pete Harnisch | | 297 | 351 | -54 |
| 1998-06-17 | vs ARI | 72 | L 1-4 | 30-42 | 6 | 20,029 | Mike Remlinger | Andy Benes | Andy Benes | Mike Remlinger | Gregg Olson | 298 | 355 | -57 |
| 1998-06-18 | vs ARI | 73 | L 2-4 | 30-43 | 6 | 21,944 | Scott Klingenbeck | Brian Anderson | Brian Anderson | Scott Klingenbeck | Gregg Olson | 300 | 359 | -59 |
| 1998-06-19 | @ HOU | 74 | L 2-4 | 30-44 | 6 | 29,251 | Scott Winchester | Sean Bergman | Sean Bergman | Scott Winchester | Billy Wagner | 302 | 363 | -61 |
| 1998-06-20 | @ HOU | 75 | L 8-9 | 30-45 | 6 | 24,301 | Brett Tomko | Scott Elarton | C.J. Nitkowski | Rick Krivda | Billy Wagner | 310 | 372 | -62 |
| 1998-06-21 | @ HOU | 76 | L 1-3 | 30-46 | 6 | 42,281 | Pete Harnisch | Pete Schourek | Pete Schourek | Pete Harnisch | Mike Magnante | 311 | 375 | -64 |
| 1998-06-22 | vs KCA | 77 | L 0-3 | 30-47 | 6 | 18,687 | Mike Remlinger | Jim Pittsley | Jim Pittsley | Mike Remlinger | Jeff Montgomery | 311 | 378 | -67 |
| 1998-06-23 | vs KCA | 78 | L 4-6 | 30-48 | 6 | 18,063 | Scott Klingenbeck | Pat Rapp | Pat Rapp | Scott Klingenbeck | Scott Service | 315 | 384 | -69 |
| 1998-06-24 | @ CHA | 79 | L 2-4 | 30-49 | 6 | 16,344 | Scott Winchester | Jaime Navarro | Jaime Navarro | Scott Winchester | Bill Simas | 317 | 388 | -71 |
| 1998-06-25 | @ CHA | 80 | W 7-5 | 31-49 | 6 | 14,081 | Brett Tomko | Jim Parque | Brett Tomko | Jim Parque | Jeff Shaw | 324 | 393 | -69 |
| 1998-06-26 | @ DET | 81 | W 4-3 | 32-49 | 6 | 25,240 | Pete Harnisch | Frank Castillo | Pete Harnisch | Doug Brocail | Jeff Shaw | 328 | 396 | -68 |
| 1998-06-27 | @ DET | 82 | W 6-5 | 33-49 | 6 | 25,356 | Mike Remlinger | Brian Powell | Gabe White | Denny Harriger | | 334 | 401 | -67 |
| 1998-06-28 | @ DET | 83 | W 5-2 | 34-49 | 6 | 22,535 | Steve Parris | Justin Thompson | Steve Parris | Justin Thompson | Jeff Shaw | 339 | 403 | -64 |
| 1998-06-30 | vs MIN | 84 | W 6-3 | 35-49 | 6 | 19,315 | Brett Tomko | LaTroy Hawkins | Brett Tomko | LaTroy Hawkins | Jeff Shaw | 345 | 406 | -61 |
| 1998-07-01 | vs MIN | 85 | L 1-2 | 35-50 | 6 | 15,592 | Scott Winchester | Brad Radke | Brad Radke | Scott Sullivan | Rick Aguilera | 346 | 408 | -62 |
| 1998-07-02 | vs MIN | 86 | W 8-7 | 36-50 | 6 | 16,528 | Pete Harnisch | Eric Milton | Jeff Shaw | Rick Aguilera | | 354 | 415 | -61 |
| 1998-07-03 | vs SLN | 87 | W 6-3 | 37-50 | 6 | 41,302 | Mike Remlinger | Todd Stottlemyre | Mike Remlinger | Todd Stottlemyre | Jeff Shaw | 360 | 418 | -58 |
| 1998-07-04 | vs SLN | 88 | W 5-4 | 38-50 | 6 | 26,200 | Steve Parris | Kent Bottenfield | Danny Graves | Rich Croushore | | 365 | 422 | -57 |
| 1998-07-05 | vs SLN | 89 | W 6-1 | 39-50 | 6 | 28,830 | Brett Tomko | Kent Mercker | Brett Tomko | Kent Mercker | | 371 | 423 | -52 |
| 1998-07-10 | @ ARI | 90 | W 5-4 | 40-50 | 6 | 45,278 | Brett Tomko | Andy Benes | Brett Tomko | Andy Benes | | 376 | 427 | -51 |
| 1998-07-11 | @ ARI | 91 | W 8-0 | 41-50 | 5 | 47,323 | Mike Remlinger | Willie Blair | Mike Remlinger | Willie Blair | | 384 | 427 | -43 |
| 1998-07-12 | @ ARI | 92 | W 5-3 | 42-50 | 5 | 42,329 | Pete Harnisch | Brian Anderson | John Hudek | Brian Anderson | | 389 | 430 | -41 |
| 1998-07-13 | @ SLN | 93 | W 6-5 | 43-50 | 5 | 37,258 | Scott Winchester | Kent Bottenfield | Gabe White | Bobby Witt | | 395 | 435 | -40 |
| 1998-07-14 | @ SLN | 94 | W 7-4 | 44-50 | 4 | 31,183 | Steve Parris | Todd Stottlemyre | Scott Sullivan | Todd Stottlemyre | Danny Graves | 402 | 439 | -37 |
| 1998-07-15 | @ SLN | 95 | W 4-2 | 45-50 | 4 | 32,321 | Brett Tomko | Matt Morris | Gabe White | John Frascatore | | 406 | 441 | -35 |
| 1998-07-17 | vs SDN | 96 | L 3-13 | 45-51 | 4 | 26,443 | Mike Remlinger | Andy Ashby | Andy Ashby | Mike Remlinger | | 409 | 454 | -45 |
| 1998-07-18 | vs SDN | 97 | L 1-2 | 45-52 | 4 | 30,289 | Pete Harnisch | Joey Hamilton | Joey Hamilton | Pete Harnisch | Trevor Hoffman | 410 | 456 | -46 |
| 1998-07-19 | vs SDN | 98 | L 6-7 | 45-53 | 5 | 23,439 | Scott Winchester | Sterling Hitchcock | Donne Wall | John Hudek | Trevor Hoffman | 416 | 463 | -47 |
| 1998-07-20 | @ LAN | 99 | L 0-2 | 45-54 | 6 | 35,775 | Steve Parris | Darren Dreifort | Darren Dreifort | Steve Parris | Jeff Shaw | 416 | 465 | -49 |
| 1998-07-21 | @ LAN | 100 | L 2-4 | 45-55 | 6 | 30,452 | Brett Tomko | Ismael Valdez | Ismael Valdez | Brett Tomko | Jeff Shaw | 418 | 469 | -51 |
| 1998-07-23 | @ COL | 101 | L 4-6 | 45-57 | 6 | 42,586 | Mike Remlinger | Pedro Astacio | Pedro Astacio | Mike Remlinger | Dave Veres | 422 | 475 | -53 |
| 1998-07-23 | @ COL | 102 | L 4-6 | 45-57 | 6 | 45,705 | Pete Harnisch | Bobby Jones | Bobby Jones | Pete Harnisch | Curt Leskanic | 426 | 481 | -55 |
| 1998-07-24 | @ SFN | 103 | L 2-12 | 45-58 | 6 | 16,931 | Scott Winchester | Mark Gardner | Mark Gardner | Scott Winchester | | 428 | 493 | -65 |
| 1998-07-25 | @ SFN | 104 | W 9-8 | 46-58 | 6 | 50,054 | Steve Parris | Russ Ortiz | Stan Belinda | Russ Ortiz | Danny Graves | 437 | 501 | -64 |
| 1998-07-26 | @ SFN | 105 | L 1-2 | 46-59 | 6 | 34,638 | Brett Tomko | Orel Hershiser | Jose Mesa | Stan Belinda | | 438 | 503 | -65 |
| 1998-07-27 | vs ATL | 106 | L 2-3 | 46-60 | 6 | 23,866 | Mike Remlinger | Tom Glavine | Rudy Seanez | Stan Belinda | Kerry Ligtenberg | 440 | 506 | -66 |
| 1998-07-28 | vs ATL | 107 | W 13-1 | 47-60 | 6 | 22,690 | Pete Harnisch | Kevin Millwood | Scott Sullivan | Kevin Millwood | | 453 | 507 | -54 |
| 1998-07-29 | vs ATL | 108 | L 5-11 | 47-61 | 6 | 24,480 | Steve Parris | John Smoltz | Rudy Seanez | Steve Parris | | 458 | 518 | -60 |
| 1998-07-30 | vs ATL | 109 | L 3-13 | 47-62 | 6 | 28,946 | Rick Krivda | Denny Neagle | Denny Neagle | Rick Krivda | | 461 | 531 | -70 |
| 1998-07-31 | @ FLO | 110 | W 3-2 | 48-62 | 6 | 16,763 | Brett Tomko | Jesus Sanchez | Brett Tomko | Matt Mantei | Gabe White | 464 | 533 | -69 |
| 1998-08-01 | @ FLO | 111 | W 9-7 | 49-62 | 6 | 24,027 | Mike Remlinger | Ryan Dempster | John Hudek | Matt Mantei | | 473 | 540 | -67 |
| 1998-08-02 | @ FLO | 112 | W 5-1 | 50-62 | 6 | 22,136 | Dennys Reyes | Kirt Ojala | Dennys Reyes | Kirt Ojala | Danny Graves | 478 | 541 | -63 |
| 1998-08-04 | @ ATL | 113 | L 2-4 | 50-63 | 6 | 43,012 | Steve Parris | John Smoltz | John Smoltz | Scott Sullivan | Kerry Ligtenberg | 480 | 545 | -65 |
| 1998-08-05 | @ ATL | 114 | W 13-9 | 51-63 | 5 | 43,315 | Brett Tomko | Denny Neagle | John Hudek | Russ Springer | | 493 | 554 | -61 |
| 1998-08-06 | @ ATL | 115 | L 0-5 | 51-64 | 5 | 47,311 | Mike Remlinger | Greg Maddux | Greg Maddux | Mike Remlinger | | 493 | 559 | -66 |
| 1998-08-07 | vs MIL | 116 | W 17-0 | 52-64 | 5 | 20,908 | Pete Harnisch | Brad Woodall | Pete Harnisch | Brad Woodall | | 510 | 559 | -49 |
| 1998-08-08 | vs MIL | 117 | W 4-0 | 53-64 | 5 | 23,906 | Dennys Reyes | Steve Woodard | Dennys Reyes | Steve Woodard | | 514 | 559 | -45 |
| 1998-08-09 | vs MIL | 118 | L 3-4 | 53-65 | 5 | 21,976 | Steve Parris | Scott Karl | Scott Karl | Steve Parris | Bob Wickman | 517 | 563 | -46 |
| 1998-08-11 | vs PIT | 119 | L 0-7 | 53-66 | 5 | 16,399 | Brett Tomko | Francisco Cordova | Francisco Cordova | Brett Tomko | | 517 | 570 | -53 |
| 1998-08-12 | vs PIT | 120 | L 4-5 | 53-67 | 6 | 16,946 | Mike Remlinger | Jason Schmidt | Jason Schmidt | Mike Remlinger | Ricardo Rincon | 521 | 575 | -54 |
| 1998-08-13 | vs PIT | 121 | L 6-9 | 53-68 | 6 | 16,002 | Pete Harnisch | Todd Van Poppel | Jeff McCurry | Pete Harnisch | Ricardo Rincon | 527 | 584 | -57 |
| 1998-08-14 | vs MON | 122 | W 3-2 | 54-68 | 6 | 19,532 | Dennys Reyes | Dustin Hermanson | Gabe White | Steve Kline | | 530 | 586 | -56 |
| 1998-08-15 | vs MON | 123 | W 6-4 | 55-68 | 5 | 24,452 | Steve Parris | Mike Thurman | Steve Parris | Mike Thurman | Gabe White | 536 | 590 | -54 |
| 1998-08-16 | vs MON | 124 | W 8-1 | 56-68 | 5 | 31,073 | Brett Tomko | Carl Pavano | Brett Tomko | Carl Pavano | | 544 | 591 | -47 |
| 1998-08-18 | @ MIL | 125 | L 4-8 | 56-69 | 6 | 15,671 | Mike Remlinger | Brad Woodall | Brad Woodall | Mike Remlinger | | 548 | 599 | -51 |
| 1998-08-19 | @ MIL | 126 | W 8-2 | 57-69 | 6 | 20,533 | Pete Harnisch | Steve Woodard | Pete Harnisch | Steve Woodard | | 556 | 601 | -45 |
| 1998-08-20 | @ PIT | 127 | L 5-6 | 57-70 | 6 | 13,137 | Dennys Reyes | Jon Lieber | Jason Christiansen | Danny Graves | | 561 | 607 | -46 |
| 1998-08-21 | @ PIT | 128 | L 2-14 | 57-71 | 6 | 17,007 | Brett Tomko | Chris Peters | Chris Peters | Brett Tomko | | 563 | 621 | -58 |
| 1998-08-22 | @ MON | 129 | W 4-0 | 58-71 | 6 | 12,795 | Steve Parris | Jeremy Powell | Steve Parris | Jeremy Powell | | 567 | 621 | -54 |
| 1998-08-23 | @ MON | 130 | W 10-0 | 59-71 | 6 | 14,371 | Jason Bere | Javier Vazquez | Jason Bere | Javier Vazquez | | 577 | 621 | -44 |
| 1998-08-24 | @ MON | 131 | W 8-1 | 60-71 | 6 | 7,537 | Pete Harnisch | Dustin Hermanson | Pete Harnisch | Dustin Hermanson | | 585 | 622 | -37 |
| 1998-08-25 | vs CHN | 132 | W 10-9 | 61-71 | 6 | 20,828 | Dennys Reyes | Kevin Tapani | John Hudek | Terry Mulholland | Gabe White | 595 | 631 | -36 |
| 1998-08-26 | vs CHN | 133 | L 2-9 | 61-72 | 6 | 20,315 | Brett Tomko | Kerry Wood | Kerry Wood | Brett Tomko | | 597 | 640 | -43 |
| 1998-08-27 | vs FLO | 134 | W 12-3 | 62-72 | 5 | 14,383 | Steve Parris | Livan Hernandez | Steve Parris | Livan Hernandez | | 609 | 643 | -34 |
| 1998-08-28 | vs FLO | 135 | W 10-8 | 63-72 | 5 | 18,293 | Jason Bere | Jesus Sanchez | Scott Sullivan | Rob Stanifer | Gabe White | 619 | 651 | -32 |
| 1998-08-29 | vs FLO | 136 | W 7-5 | 64-72 | 4 | 22,445 | Pete Harnisch | Brian Meadows | Mike Remlinger | Brian Meadows | Danny Graves | 626 | 656 | -30 |
| 1998-08-30 | vs FLO | 137 | W 14-7 | 65-72 | 4 | 18,426 | Dennys Reyes | Rafael Medina | Dennys Reyes | Rafael Medina | | 640 | 663 | -23 |
| 1998-08-31 | @ CHN | 138 | L 4-5 | 65-73 | 4 | 36,700 | Brett Tomko | Kerry Wood | Kerry Wood | Brett Tomko | Rod Beck | 644 | 668 | -24 |
| 1998-09-01 | @ CHN | 139 | L 5-6 | 65-74 | 5 | 38,223 | Steve Parris | Mike Morgan | Matt Karchner | Gabe White | Rod Beck | 649 | 674 | -25 |
| 1998-09-02 | @ CHN | 140 | L 2-4 | 65-75 | 6 | 36,761 | Jason Bere | Steve Trachsel | Felix Heredia | Gabe White | Rod Beck | 651 | 678 | -27 |
| 1998-09-04 | @ SLN | 141 | W 3-2 | 66-75 | 4 | 48,076 | Pete Harnisch | Kent Bottenfield | Pete Harnisch | John Frascatore | Gabe White | 654 | 680 | -26 |
| 1998-09-05 | @ SLN | 142 | L 0-7 | 66-76 | 5 | 47,994 | Dennys Reyes | Donovan Osborne | Donovan Osborne | Dennys Reyes | | 654 | 687 | -33 |
| 1998-09-06 | @ SLN | 143 | L 2-5 | 66-77 | 6 | 47,904 | Brett Tomko | Matt Morris | Juan Acevedo | John Hudek | | 656 | 692 | -36 |
| 1998-09-07 | @ HOU | 144 | L 0-1 | 66-78 | 6 | 42,787 | Steve Parris | Randy Johnson | Randy Johnson | Steve Parris | | 656 | 693 | -37 |
| 1998-09-08 | @ HOU | 145 | L 7-13 | 66-79 | 6 | 16,574 | Jason Bere | Sean Bergman | Sean Bergman | Jason Bere | | 663 | 706 | -43 |
| 1998-09-09 | vs SLN | 146 | W 6-3 | 67-79 | 6 | 51,969 | Pete Harnisch | Bobby Witt | Pete Harnisch | Bobby Witt | Danny Graves | 669 | 709 | -40 |
| 1998-09-10 | vs SLN | 147 | L 7-8 | 67-80 | 6 | 50,971 | Mike Remlinger | Donovan Osborne | Manny Aybar | Mike Remlinger | Juan Acevedo | 676 | 717 | -41 |
| 1998-09-11 | vs ARI | 148 | W 13-1 | 68-80 | 6 | 16,579 | Brett Tomko | Clint Sodowsky | Brett Tomko | Clint Sodowsky | | 689 | 718 | -29 |
| 1998-09-12 | vs ARI | 149 | W 3-0 | 69-80 | 5 | 17,463 | Steve Parris | Omar Daal | Steve Parris | Omar Daal | Gabe White | 692 | 718 | -26 |
| 1998-09-13 | vs ARI | 150 | L 0-5 | 69-81 | 5 | 17,741 | Jason Bere | Andy Benes | Andy Benes | Jason Bere | Gregg Olson | 692 | 723 | -31 |
| 1998-09-14 | vs MIL | 151 | L 1-2 | 69-82 | 5 | 13,291 | Pete Harnisch | Steve Woodard | Steve Woodard | Pete Harnisch | Bob Wickman | 693 | 725 | -32 |
| 1998-09-15 | vs MIL | 152 | W 5-1 | 70-82 | 5 | 13,785 | Mike Remlinger | Scott Karl | Mike Remlinger | Scott Karl | Danny Graves | 698 | 726 | -28 |
| 1998-09-16 | vs MIL | 153 | L 0-2 | 70-83 | 5 | 14,467 | Brett Tomko | Bill Pulsipher | Bill Pulsipher | Brett Tomko | Bob Wickman | 698 | 728 | -30 |
| 1998-09-18 | @ CHN | 154 | W 6-4 | 71-83 | 5 | 40,105 | Steve Parris | Steve Trachsel | Steve Parris | Don Wengert | Gabe White | 704 | 732 | -28 |
| 1998-09-19 | @ CHN | 155 | W 7-2 | 72-83 | 4 | 40,357 | Jason Bere | Mark Clark | Jason Bere | Mark Clark | | 711 | 734 | -23 |
| 1998-09-20 | @ CHN | 156 | W 7-3 | 73-83 | 4 | 40,117 | Pete Harnisch | Kevin Tapani | Pete Harnisch | Kevin Tapani | Gabe White | 718 | 737 | -19 |
| 1998-09-21 | vs PHI | 157 | W 8-5 | 74-83 | 4 | 12,969 | Mike Remlinger | Tyler Green | Scott Sullivan | Mark Leiter | Danny Graves | 726 | 742 | -16 |
| 1998-09-22 | vs PHI | 158 | L 8-10 | 74-84 | 4 | 13,644 | Brett Tomko | Carlton Loewer | Jerry Spradlin | Todd Williams | Ricky Bottalico | 734 | 752 | -18 |
| 1998-09-23 | vs PHI | 159 | L 2-4 | 74-85 | 4 | 13,376 | Steve Parris | Mark Portugal | Mark Portugal | Steve Parris | Ricky Bottalico | 736 | 756 | -20 |
| 1998-09-25 | vs PIT | 160 | W 4-1 | 75-85 | 4 | 17,429 | Jason Bere | Francisco Cordova | Jason Bere | Francisco Cordova | Danny Graves | 740 | 757 | -17 |
| 1998-09-26 | vs PIT | 161 | W 6-2 | 76-85 | 4 | 19,391 | Pete Harnisch | Jason Schmidt | Pete Harnisch | Jason Schmidt | Gabe White | 746 | 759 | -13 |
| 1998-09-27 | vs PIT | 162 | W 4-1 | 77-85 | 4 | 19,360 | Brett Tomko | Jose Silva | Brett Tomko | Jose Silva | | 750 | 760 | -10 |