| 1999-04-04 | vs COL | 1 | L 2-8 | 0-1 | 2 | 27,104 | Andy Ashby | Darryl Kile | Darryl Kile | Andy Ashby | | 2 | 8 | -6 |
| 1999-04-06 | vs COL | 2 | W 4-3 | 1-1 | 3 | 61,247 | Sterling Hitchcock | Pedro Astacio | Sterling Hitchcock | Pedro Astacio | Trevor Hoffman | 6 | 11 | -5 |
| 1999-04-07 | vs COL | 3 | W 2-1 | 2-1 | 2 | 32,751 | Woody Williams | Jamey Wright | Roberto Rivera | Bobby Jones | | 8 | 12 | -4 |
| 1999-04-08 | @ SFN | 4 | L 4-12 | 3-1 | 2 | 57,430 | Stan Spencer | Shawn Estes | Shawn Estes | Stan Spencer | | 12 | 24 | -12 |
| 1999-04-09 | @ SFN | 5 | L 3-8 | 3-2 | 2 | 15,795 | Matt Clement | Chris Brock | Chris Brock | Matt Clement | | 15 | 32 | -17 |
| 1999-04-10 | @ SFN | 6 | W 11-1 | 4-2 | 2 | 18,331 | Andy Ashby | Mark Gardner | Andy Ashby | Mark Gardner | | 26 | 33 | -7 |
| 1999-04-11 | @ SFN | 7 | L 6-8 | 4-3 | 2 | 22,330 | Sterling Hitchcock | Kirk Rueter | John Johnstone | Roberto Rivera | Robb Nen | 32 | 41 | -9 |
| 1999-04-12 | @ COL | 8 | W 8-5 | 5-3 | 2 | 48,073 | Woody Williams | Pedro Astacio | Donne Wall | Dave Veres | Carlos Reyes | 40 | 46 | -6 |
| 1999-04-15 | @ COL | 9 | L 4-6 | 5-4 | 2 | 40,027 | Matt Clement | Brian Bohanon | Brian Bohanon | Matt Clement | Dave Veres | 44 | 52 | -8 |
| 1999-04-16 | vs LAN | 10 | W 3-0 | 6-4 | 2 | 48,943 | Andy Ashby | Kevin Brown | Andy Ashby | Kevin Brown | | 47 | 52 | -5 |
| 1999-04-17 | vs LAN | 11 | L 3-7 | 6-5 | 3 | 56,568 | Sterling Hitchcock | Chan Ho Park | Chan Ho Park | Carlos Reyes | | 50 | 59 | -9 |
| 1999-04-18 | vs LAN | 12 | W 4-3 | 7-5 | 3 | 51,341 | Woody Williams | Ismael Valdez | Dan Miceli | Onan Masaoka | Trevor Hoffman | 54 | 62 | -8 |
| 1999-04-19 | vs PIT | 13 | L 0-3 | 7-6 | 4 | 33,616 | Stan Spencer | Pete Schourek | Pete Schourek | Stan Spencer | Jason Christiansen | 54 | 65 | -11 |
| 1999-04-20 | vs PIT | 14 | L 3-7 | 7-7 | 4 | 15,439 | Matt Clement | Kris Benson | Mike Williams | Trevor Hoffman | | 57 | 72 | -15 |
| 1999-04-21 | vs PIT | 15 | W 2-0 | 8-7 | 4 | 13,928 | Andy Ashby | Jason Schmidt | Andy Ashby | Jason Schmidt | Trevor Hoffman | 59 | 72 | -13 |
| 1999-04-23 | vs ARI | 16 | L 6-10 | 9-7 | 3 | 20,437 | Sterling Hitchcock | Andy Benes | Andy Benes | Sterling Hitchcock | | 65 | 82 | -17 |
| 1999-04-24 | vs ARI | 17 | W 7-2 | 10-7 | 3 | 61,674 | Woody Williams | Omar Daal | Woody Williams | Omar Daal | | 72 | 84 | -12 |
| 1999-04-25 | vs ARI | 18 | L 3-5 | 10-8 | 3 | 26,684 | Stan Spencer | Randy Johnson | Greg Swindell | Dan Miceli | Gregg Olson | 75 | 89 | -14 |
| 1999-04-27 | @ NYN | 19 | W 6-2 | 11-8 | 3 | 25,113 | Andy Ashby | Masato Yoshii | Andy Ashby | Masato Yoshii | | 81 | 91 | -10 |
| 1999-04-28 | @ NYN | 20 | L 3-4 | 11-9 | 3 | 22,581 | Sterling Hitchcock | Al Leiter | Turk Wendell | Trevor Hoffman | | 84 | 95 | -11 |
| 1999-04-29 | @ NYN | 21 | L 5-8 | 11-10 | 3 | 18,442 | Woody Williams | Bobby Jones | Dennis Cook | Brian Boehringer | John Franco | 89 | 103 | -14 |
| 1999-04-30 | @ CHN | 22 | L 5-6 | 11-11 | 4 | 24,187 | Stan Spencer | Terry Mulholland | Terry Mulholland | Stan Spencer | Rod Beck | 94 | 109 | -15 |
| 1999-05-01 | @ CHN | 23 | L 1-2 | 11-12 | 4 | 38,956 | Matt Clement | Kevin Tapani | Kevin Tapani | Matt Clement | Felix Heredia | 95 | 111 | -16 |
| 1999-05-02 | @ CHN | 24 | L 2-3 | 11-13 | 4 | 38,486 | Andy Ashby | Scott Sanders | Rodney Myers | Roberto Rivera | Rod Beck | 97 | 114 | -17 |
| 1999-05-03 | @ PHI | 25 | W 9-3 | 12-13 | 4 | 11,032 | Sterling Hitchcock | Chad Ogea | Sterling Hitchcock | Chad Ogea | | 106 | 117 | -11 |
| 1999-05-04 | @ PHI | 26 | L 0-3 | 12-14 | 4 | 15,183 | Woody Williams | Carlton Loewer | Carlton Loewer | Woody Williams | | 106 | 120 | -14 |
| 1999-05-05 | @ PHI | 27 | L 1-11 | 12-15 | 4 | 18,229 | Stan Spencer | Paul Byrd | Paul Byrd | Stan Spencer | | 107 | 131 | -24 |
| 1999-05-07 | vs ATL | 28 | W 4-3 | 13-15 | 3 | 26,765 | Matt Clement | Kevin Millwood | Brian Boehringer | John Rocker | Trevor Hoffman | 111 | 134 | -23 |
| 1999-05-08 | vs ATL | 29 | L 1-11 | 13-16 | 3 | 52,973 | Andy Ashby | Tom Glavine | Tom Glavine | Andy Ashby | | 112 | 145 | -33 |
| 1999-05-09 | vs ATL | 30 | W 5-0 | 14-16 | 3 | 23,711 | Sterling Hitchcock | Greg Maddux | Sterling Hitchcock | Greg Maddux | | 117 | 145 | -28 |
| 1999-05-10 | vs FLO | 31 | W 7-5 | 15-16 | 3 | 12,713 | Woody Williams | Brian Meadows | Dan Miceli | Antonio Alfonseca | Trevor Hoffman | 124 | 150 | -26 |
| 1999-05-11 | vs FLO | 32 | L 4-5 | 15-17 | 3 | 14,188 | Stan Spencer | Ryan Dempster | Ryan Dempster | Stan Spencer | Matt Mantei | 128 | 155 | -27 |
| 1999-05-12 | vs FLO | 33 | W 8-7 | 16-17 | 3 | 14,288 | Matt Clement | Dennis Springer | Donne Wall | Brian Edmondson | Trevor Hoffman | 136 | 162 | -26 |
| 1999-05-14 | @ CIN | 34 | W 7-3 | 17-17 | 3 | 20,877 | Andy Ashby | Denny Neagle | Andy Ashby | Denny Neagle | Trevor Hoffman | 143 | 165 | -22 |
| 1999-05-15 | @ CIN | 35 | L 2-6 | 17-18 | 3 | 25,715 | Sterling Hitchcock | Steve Parris | Steve Parris | Sterling Hitchcock | Scott Williamson | 145 | 171 | -26 |
| 1999-05-16 | @ CIN | 36 | L 0-3 | 17-19 | 4 | 26,843 | Woody Williams | Brett Tomko | Brett Tomko | Woody Williams | Scott Williamson | 145 | 174 | -29 |
| 1999-05-18 | vs SLN | 37 | L 2-5 | 17-20 | 3 | 29,222 | Matt Clement | Darren Oliver | Darren Oliver | Matt Clement | Ricky Bottalico | 147 | 179 | -32 |
| 1999-05-19 | vs SLN | 38 | W 7-6 | 18-20 | 3 | 31,686 | Andy Ashby | Jose Jimenez | Brian Boehringer | Ricky Bottalico | | 154 | 185 | -31 |
| 1999-05-20 | vs SLN | 39 | L 4-6 | 18-21 | 3 | 33,316 | Sterling Hitchcock | Kent Bottenfield | Kent Bottenfield | Sterling Hitchcock | Ricky Bottalico | 158 | 191 | -33 |
| 1999-05-21 | vs CIN | 40 | W 5-4 | 19-21 | 3 | 21,951 | Woody Williams | Brett Tomko | Woody Williams | Brett Tomko | Trevor Hoffman | 163 | 195 | -32 |
| 1999-05-22 | vs CIN | 41 | L 0-3 | 19-22 | 3 | 49,465 | Heath Murray | Pete Harnisch | Pete Harnisch | Heath Murray | | 163 | 198 | -35 |
| 1999-05-23 | vs CIN | 42 | L 2-6 | 19-23 | 4 | 32,761 | Matt Clement | Steve Avery | Steve Avery | Matt Clement | Scott Williamson | 165 | 204 | -39 |
| 1999-05-24 | @ ARI | 43 | L 5-6 | 19-24 | 4 | 34,745 | Andy Ashby | Andy Benes | Andy Benes | Andy Ashby | Gregg Olson | 170 | 210 | -40 |
| 1999-05-25 | @ ARI | 44 | L 0-4 | 19-25 | 4 | 34,273 | Sterling Hitchcock | Randy Johnson | Randy Johnson | Sterling Hitchcock | | 170 | 214 | -44 |
| 1999-05-26 | @ ARI | 45 | L 2-3 | 19-26 | 4 | 33,048 | Woody Williams | Brian Anderson | Gregg Olson | Dan Miceli | | 172 | 217 | -45 |
| 1999-05-28 | @ MIL | 46 | W 10-8 | 19-27 | 5 | 16,065 | Heath Murray | Cal Eldred | Carlos Reyes | Cal Eldred | Trevor Hoffman | 182 | 225 | -43 |
| 1999-05-29 | @ MIL | 47 | W 12-3 | 19-28 | 5 | 18,614 | Matt Clement | Steve Woodard | Matt Clement | Steve Woodard | | 194 | 228 | -34 |
| 1999-05-30 | @ MIL | 48 | L 3-10 | 20-28 | 5 | 19,002 | Sterling Hitchcock | Jim Abbott | Jim Abbott | Sterling Hitchcock | | 197 | 238 | -41 |
| 1999-05-31 | @ MIL | 49 | L 2-8 | 20-29 | 5 | 14,985 | Woody Williams | Hideo Nomo | Hideo Nomo | Woody Williams | | 199 | 246 | -47 |
| 1999-06-01 | @ CHN | 50 | W 1-0 | 21-29 | 5 | 34,344 | Andy Ashby | Steve Trachsel | Andy Ashby | Steve Trachsel | | 200 | 246 | -46 |
| 1999-06-02 | @ CHN | 51 | L 8-9 | 21-30 | 5 | 28,742 | Heath Murray | Kyle Farnsworth | Scott Sanders | Trevor Hoffman | | 208 | 255 | -47 |
| 1999-06-03 | @ CHN | 52 | L 2-7 | 21-31 | 5 | 33,920 | Matt Clement | Kevin Tapani | Kevin Tapani | Matt Clement | | 210 | 262 | -52 |
| 1999-06-04 | vs SEA | 53 | W 3-2 | 22-31 | 5 | 26,060 | Sterling Hitchcock | Jeff Fassero | Donne Wall | Jose Paniagua | Trevor Hoffman | 213 | 264 | -51 |
| 1999-06-05 | vs SEA | 54 | W 3-2 | 23-31 | 5 | 52,539 | Woody Williams | Jamie Moyer | Carlos Reyes | Jose Mesa | | 216 | 266 | -50 |
| 1999-06-06 | vs SEA | 55 | L 1-4 | 23-32 | 5 | 31,761 | Andy Ashby | Freddy Garcia | Freddy Garcia | Andy Ashby | Jose Paniagua | 217 | 270 | -53 |
| 1999-06-08 | vs OAK | 56 | W 5-3 | 24-32 | 5 | 17,195 | Heath Murray | Tim Hudson | Donne Wall | Buddy Groom | Trevor Hoffman | 222 | 273 | -51 |
| 1999-06-09 | vs OAK | 57 | L 0-3 | 24-33 | 5 | 15,896 | Matt Clement | Jimmy Haynes | Jimmy Haynes | Matt Clement | Billy Taylor | 222 | 276 | -54 |
| 1999-06-10 | vs OAK | 58 | W 2-1 | 25-33 | 5 | 20,024 | Sterling Hitchcock | Gil Heredia | Sterling Hitchcock | Gil Heredia | Trevor Hoffman | 224 | 277 | -53 |
| 1999-06-11 | @ HOU | 59 | L 1-2 | 25-34 | 5 | 38,425 | Woody Williams | Sean Bergman | Sean Bergman | Woody Williams | Billy Wagner | 225 | 279 | -54 |
| 1999-06-12 | @ HOU | 60 | L 2-3 | 25-35 | 5 | 39,893 | Brian Boehringer | Jose Lima | Jose Lima | Donne Wall | Billy Wagner | 227 | 282 | -55 |
| 1999-06-13 | @ HOU | 61 | L 3-4 | 25-36 | 5 | 39,773 | Heath Murray | Shane Reynolds | Shane Reynolds | Heath Murray | Billy Wagner | 230 | 286 | -56 |
| 1999-06-15 | vs PHI | 62 | W 6-1 | 26-36 | 5 | 16,134 | Matt Clement | Chad Ogea | Matt Clement | Chad Ogea | | 236 | 287 | -51 |
| 1999-06-16 | vs PHI | 63 | L 2-4 | 26-37 | 5 | 15,136 | Sterling Hitchcock | Randy Wolf | Randy Wolf | Sterling Hitchcock | Wayne Gomes | 238 | 291 | -53 |
| 1999-06-17 | vs PHI | 64 | L 5-7 | 26-38 | 5 | 16,671 | Woody Williams | Paul Byrd | Paul Byrd | Woody Williams | Wayne Gomes | 243 | 298 | -55 |
| 1999-06-18 | vs PIT | 65 | W 4-2 | 27-38 | 5 | 60,799 | Brian Boehringer | Jose Silva | Brian Boehringer | Jose Silva | Trevor Hoffman | 247 | 300 | -53 |
| 1999-06-19 | vs PIT | 66 | W 5-4 | 28-38 | 5 | 33,803 | Heath Murray | Jason Schmidt | Will Cunnane | Jason Schmidt | Trevor Hoffman | 252 | 304 | -52 |
| 1999-06-20 | vs PIT | 67 | W 6-3 | 29-38 | 5 | 25,819 | Matt Clement | Todd Ritchie | Matt Clement | Todd Ritchie | Trevor Hoffman | 258 | 307 | -49 |
| 1999-06-22 | @ LAN | 68 | W 4-1 | 30-38 | 5 | 37,366 | Sterling Hitchcock | Chan Ho Park | Sterling Hitchcock | Chan Ho Park | Trevor Hoffman | 262 | 308 | -46 |
| 1999-06-23 | @ LAN | 69 | W 6-2 | 31-38 | 4 | 31,152 | Woody Williams | Ismael Valdez | Woody Williams | Ismael Valdez | Trevor Hoffman | 268 | 310 | -42 |
| 1999-06-24 | @ LAN | 70 | W 2-1 | 32-38 | 4 | 31,028 | Andy Ashby | Darren Dreifort | Andy Ashby | Darren Dreifort | Dan Miceli | 270 | 311 | -41 |
| 1999-06-25 | vs COL | 71 | W 10-1 | 33-38 | 4 | 22,362 | Brian Boehringer | Brian Bohanon | Brian Boehringer | Brian Bohanon | | 280 | 312 | -32 |
| 1999-06-26 | vs COL | 72 | W 13-6 | 33-39 | 4 | 47,808 | Matt Clement | Mark Brownson | Matt Clement | Mark Brownson | | 293 | 318 | -25 |
| 1999-06-27 | vs COL | 73 | W 5-3 | 34-39 | 4 | 25,177 | Sterling Hitchcock | Darryl Kile | Sterling Hitchcock | Darryl Kile | Trevor Hoffman | 298 | 321 | -23 |
| 1999-06-28 | vs COL | 74 | W 8-7 | 35-39 | 4 | 41,107 | Woody Williams | Pedro Astacio | Woody Williams | Pedro Astacio | Trevor Hoffman | 306 | 328 | -22 |
| 1999-06-29 | vs LAN | 75 | W 4-3 | 36-39 | 3 | 36,398 | Andy Ashby | Ismael Valdez | Donne Wall | Mike Maddux | | 310 | 331 | -21 |
| 1999-06-30 | vs LAN | 76 | W 11-2 | 36-40 | 3 | 44,965 | Brian Boehringer | Kevin Brown | Brian Boehringer | Kevin Brown | | 321 | 333 | -12 |
| 1999-07-01 | vs LAN | 77 | W 6-3 | 37-40 | 3 | 38,080 | Matt Clement | Darren Dreifort | Matt Clement | Darren Dreifort | Trevor Hoffman | 327 | 336 | -9 |
| 1999-07-02 | @ COL | 78 | W 15-3 | 37-41 | 3 | 41,739 | Sterling Hitchcock | Pedro Astacio | Sterling Hitchcock | Pedro Astacio | | 342 | 339 | 3 |
| 1999-07-03 | @ COL | 79 | L 10-12 | 37-43 | 6 | 38,375 | Woody Williams | Roberto Ramirez | Roberto Ramirez | Woody Williams | Dave Veres | 352 | 351 | 1 |
| 1999-07-03 | @ COL | 80 | L 6-8 | 37-43 | 6 | 48,750 | Heath Murray | Bobby Jones | Bobby Jones | Heath Murray | Dave Veres | 358 | 359 | -1 |
| 1999-07-04 | @ COL | 81 | W 11-0 | 38-43 | 4 | 38,059 | Andy Ashby | Brian Bohanon | Andy Ashby | Brian Bohanon | | 369 | 359 | 10 |
| 1999-07-05 | vs SFN | 82 | L 1-4 | 38-44 | 4 | 58,333 | Brian Boehringer | Russ Ortiz | Russ Ortiz | Brian Boehringer | | 370 | 363 | 7 |
| 1999-07-06 | vs SFN | 83 | L 9-10 | 39-44 | 4 | 25,435 | Matt Clement | Shawn Estes | Shawn Estes | Matt Clement | John Johnstone | 379 | 373 | 6 |
| 1999-07-07 | vs SFN | 84 | W 5-2 | 40-44 | 4 | 22,403 | Sterling Hitchcock | Chris Brock | Sterling Hitchcock | Chris Brock | Trevor Hoffman | 384 | 375 | 9 |
| 1999-07-09 | vs TEX | 85 | L 2-7 | 40-45 | 4 | 25,546 | Woody Williams | Aaron Sele | Aaron Sele | Woody Williams | | 386 | 382 | 4 |
| 1999-07-10 | vs TEX | 86 | W 5-4 | 41-45 | 4 | 49,123 | Andy Ashby | Mike Morgan | Donne Wall | John Wetteland | | 391 | 386 | 5 |
| 1999-07-11 | vs TEX | 87 | W 6-2 | 42-45 | 4 | 31,301 | Matt Clement | John Burkett | Dan Miceli | Esteban Loaiza | | 397 | 388 | 9 |
| 1999-07-15 | @ SEA | 88 | W 3-2 | 43-45 | 4 | 44,607 | Andy Ashby | Jamie Moyer | Will Cunnane | Jose Mesa | Dan Miceli | 400 | 390 | 10 |
| 1999-07-16 | @ SEA | 89 | W 2-1 | 44-45 | 4 | 43,252 | Sterling Hitchcock | Jeff Fassero | Sterling Hitchcock | Jeff Fassero | Trevor Hoffman | 402 | 391 | 11 |
| 1999-07-17 | @ SEA | 90 | L 1-9 | 44-46 | 4 | 44,077 | Woody Williams | Freddy Garcia | Freddy Garcia | Woody Williams | | 403 | 400 | 3 |
| 1999-07-18 | @ ANA | 91 | W 6-3 | 45-46 | 4 | 37,697 | Brian Boehringer | Mike Fyhrie | Brian Boehringer | Mike Fyhrie | Trevor Hoffman | 409 | 403 | 6 |
| 1999-07-19 | @ ANA | 92 | W 4-1 | 46-46 | 3 | 25,217 | Matt Clement | Ken Hill | Dan Miceli | Shigetoshi Hasegawa | Trevor Hoffman | 413 | 404 | 9 |
| 1999-07-20 | @ ANA | 93 | W 2-1 | 47-46 | 2 | 35,247 | Andy Ashby | Chuck Finley | Andy Ashby | Mark Petkovsek | Trevor Hoffman | 415 | 405 | 10 |
| 1999-07-21 | @ SFN | 94 | L 2-10 | 48-46 | 2 | 19,616 | Sterling Hitchcock | Russ Ortiz | Russ Ortiz | Sterling Hitchcock | | 417 | 415 | 2 |
| 1999-07-22 | @ SFN | 95 | W 8-7 | 49-46 | 3 | 22,455 | Woody Williams | Kirk Rueter | Woody Williams | Kirk Rueter | Trevor Hoffman | 425 | 422 | 3 |
| 1999-07-23 | @ HOU | 96 | L 4-7 | 49-47 | 3 | 37,482 | Brian Boehringer | Mike Hampton | Mike Hampton | Donne Wall | | 429 | 429 | 0 |
| 1999-07-24 | @ HOU | 97 | L 2-5 | 49-48 | 3 | 36,115 | Matt Clement | Chris Holt | Chris Holt | Matt Clement | Billy Wagner | 431 | 434 | -3 |
| 1999-07-25 | @ HOU | 98 | L 2-5 | 49-49 | 3 | 34,613 | Andy Ashby | Shane Reynolds | Shane Reynolds | Andy Ashby | | 433 | 439 | -6 |
| 1999-07-26 | vs ARI | 99 | L 0-2 | 49-50 | 3 | 20,042 | Sterling Hitchcock | Armando Reynoso | Armando Reynoso | Sterling Hitchcock | Matt Mantei | 433 | 441 | -8 |
| 1999-07-27 | vs ARI | 100 | L 3-4 | 49-51 | 3 | 29,224 | Woody Williams | Andy Benes | Gregg Olson | Carlos Reyes | Matt Mantei | 436 | 445 | -9 |
| 1999-07-28 | vs ARI | 101 | L 4-7 | 49-52 | 3 | 28,806 | Brian Boehringer | Omar Daal | Omar Daal | Brian Boehringer | Dan Plesac | 440 | 452 | -12 |
| 1999-07-30 | vs HOU | 102 | L 1-5 | 49-53 | 3 | 39,619 | Matt Clement | Shane Reynolds | Shane Reynolds | Matt Clement | | 441 | 457 | -16 |
| 1999-07-31 | vs HOU | 103 | L 5-8 | 49-54 | 3 | 60,516 | Andy Ashby | Scott Elarton | Doug Henry | Dan Miceli | | 446 | 465 | -19 |
| 1999-08-01 | vs HOU | 104 | W 10-3 | 49-55 | 3 | 32,294 | Sterling Hitchcock | Jose Lima | Sterling Hitchcock | Jose Lima | | 456 | 468 | -12 |
| 1999-08-02 | @ SLN | 105 | L 5-6 | 49-56 | 3 | 35,202 | Woody Williams | Kent Bottenfield | Kent Bottenfield | Woody Williams | Rich Croushore | 461 | 474 | -13 |
| 1999-08-03 | @ SLN | 106 | L 0-6 | 49-57 | 4 | 40,652 | Brian Boehringer | Darren Oliver | Darren Oliver | Brian Boehringer | | 461 | 480 | -19 |
| 1999-08-04 | @ SLN | 107 | L 6-7 | 49-58 | 4 | 43,546 | Matt Clement | Kent Mercker | Heathcliff Slocumb | Donne Wall | Rich Croushore | 467 | 487 | -20 |
| 1999-08-05 | @ SLN | 108 | W 10-3 | 49-59 | 4 | 45,106 | Andy Ashby | Larry Luebbers | Andy Ashby | Larry Luebbers | Trevor Hoffman | 477 | 490 | -13 |
| 1999-08-06 | @ MON | 109 | W 12-10 | 50-59 | 4 | 13,540 | Sterling Hitchcock | Dan Smith | Sterling Hitchcock | Dan Smith | Trevor Hoffman | 489 | 500 | -11 |
| 1999-08-07 | @ MON | 110 | L 1-3 | 50-60 | 4 | 25,104 | Woody Williams | Dustin Hermanson | Dustin Hermanson | Woody Williams | Ugueth Urbina | 490 | 503 | -13 |
| 1999-08-08 | @ MON | 111 | L 2-4 | 50-61 | 5 | 9,925 | Brian Boehringer | Javier Vazquez | Steve Kline | Carlos Reyes | Ugueth Urbina | 492 | 507 | -15 |
| 1999-08-09 | @ MON | 112 | L 0-8 | 50-62 | 5 | 7,545 | Matt Clement | Jeremy Powell | Jeremy Powell | Matt Clement | | 492 | 515 | -23 |
| 1999-08-10 | @ NYN | 113 | L 3-4 | 50-63 | 5 | 32,101 | Andy Ashby | Kenny Rogers | Turk Wendell | Andy Ashby | Armando Benitez | 495 | 519 | -24 |
| 1999-08-11 | @ NYN | 114 | L 5-12 | 51-63 | 5 | 34,232 | Sterling Hitchcock | Octavio Dotel | Pat Mahomes | Sterling Hitchcock | | 500 | 531 | -31 |
| 1999-08-12 | @ NYN | 115 | L 3-9 | 51-64 | 5 | 32,062 | Woody Williams | Al Leiter | Al Leiter | Woody Williams | | 503 | 540 | -37 |
| 1999-08-13 | vs FLO | 116 | L 3-4 | 51-65 | 6 | 48,743 | Brian Boehringer | Brian Meadows | Brian Meadows | Brian Boehringer | Antonio Alfonseca | 506 | 544 | -38 |
| 1999-08-14 | vs FLO | 117 | W 6-4 | 52-65 | 5 | 61,355 | Matt Clement | Ryan Dempster | Matt Clement | Jesus Sanchez | Trevor Hoffman | 512 | 548 | -36 |
| 1999-08-15 | vs FLO | 118 | W 7-6 | 53-65 | 6 | 26,325 | Andy Ashby | Dennis Springer | Andy Ashby | Dennis Springer | Trevor Hoffman | 519 | 554 | -35 |
| 1999-08-16 | vs NYN | 119 | L 3-4 | 53-66 | 5 | 21,974 | Sterling Hitchcock | Octavio Dotel | Dennis Cook | Will Cunnane | Armando Benitez | 522 | 558 | -36 |
| 1999-08-17 | vs NYN | 120 | W 3-2 | 54-66 | 5 | 22,790 | Woody Williams | Al Leiter | Woody Williams | Al Leiter | Trevor Hoffman | 525 | 560 | -35 |
| 1999-08-18 | vs NYN | 121 | L 1-9 | 54-67 | 5 | 24,519 | Stan Spencer | Masato Yoshii | Masato Yoshii | Stan Spencer | | 526 | 569 | -43 |
| 1999-08-20 | @ ATL | 122 | L 3-4 | 54-68 | 5 | 48,201 | Matt Clement | Tom Glavine | Mike Remlinger | Carlos Reyes | | 529 | 573 | -44 |
| 1999-08-21 | @ ATL | 123 | L 2-6 | 54-69 | 5 | 48,362 | Andy Ashby | Greg Maddux | Greg Maddux | Andy Ashby | | 531 | 579 | -48 |
| 1999-08-22 | @ ATL | 124 | L 2-3 | 54-70 | 5 | 33,847 | Sterling Hitchcock | Terry Mulholland | John Rocker | Dan Miceli | | 533 | 582 | -49 |
| 1999-08-23 | @ PHI | 125 | W 7-6 | 55-70 | 5 | 18,759 | Woody Williams | Chad Ogea | Woody Williams | Chad Ogea | Trevor Hoffman | 540 | 588 | -48 |
| 1999-08-24 | @ PHI | 126 | L 2-18 | 56-70 | 5 | 18,126 | Stan Spencer | Paul Byrd | Paul Byrd | Stan Spencer | | 542 | 606 | -64 |
| 1999-08-25 | @ PHI | 127 | L 1-15 | 56-71 | 6 | 25,539 | Matt Clement | Robert Person | Robert Person | Matt Clement | | 543 | 621 | -78 |
| 1999-08-26 | vs MIL | 128 | W 4-3 | 57-71 | 5 | 22,343 | Andy Ashby | Kyle Peterson | Andy Ashby | Rocky Coppinger | Trevor Hoffman | 547 | 624 | -77 |
| 1999-08-27 | vs MIL | 129 | W 8-7 | 58-71 | 5 | 18,607 | Sterling Hitchcock | Cal Eldred | Matt Whiteside | Bob Wickman | | 555 | 631 | -76 |
| 1999-08-28 | vs MIL | 130 | L 4-6 | 58-72 | 6 | 30,199 | Woody Williams | Hideo Nomo | Hideo Nomo | Woody Williams | Bob Wickman | 559 | 637 | -78 |
| 1999-08-29 | vs MIL | 131 | W 5-4 | 59-72 | 5 | 22,997 | Buddy Carlyle | Scott Karl | Trevor Hoffman | Bob Wickman | | 564 | 641 | -77 |
| 1999-08-30 | vs CHN | 132 | W 8-4 | 60-72 | 5 | 21,874 | Matt Clement | Jon Lieber | Donne Wall | Felix Heredia | | 572 | 645 | -73 |
| 1999-08-31 | vs CHN | 133 | W 7-3 | 61-72 | 5 | 24,935 | Andy Ashby | Micah Bowie | Andy Ashby | Micah Bowie | | 579 | 648 | -69 |
| 1999-09-01 | vs CHN | 134 | L 0-1 | 61-73 | 5 | 31,132 | Sterling Hitchcock | Steve Trachsel | Steve Trachsel | Sterling Hitchcock | Terry Adams | 579 | 649 | -70 |
| 1999-09-03 | @ FLO | 135 | W 6-3 | 62-73 | 5 | 12,581 | Woody Williams | A.J. Burnett | Woody Williams | A.J. Burnett | Trevor Hoffman | 585 | 652 | -67 |
| 1999-09-04 | @ FLO | 136 | L 4-6 | 62-74 | 5 | 25,478 | Buddy Carlyle | Alex Fernandez | Alex Fernandez | Buddy Carlyle | Antonio Alfonseca | 589 | 658 | -69 |
| 1999-09-05 | @ FLO | 137 | W 5-2 | 63-74 | 5 | 15,875 | Matt Clement | Vladimir Nunez | Matt Clement | Vladimir Nunez | Trevor Hoffman | 594 | 660 | -66 |
| 1999-09-06 | @ PIT | 138 | W 4-3 | 64-74 | 5 | 16,663 | Andy Ashby | Todd Ritchie | Andy Ashby | Todd Ritchie | Trevor Hoffman | 598 | 663 | -65 |
| 1999-09-07 | @ PIT | 139 | L 1-3 | 64-75 | 5 | 11,058 | Sterling Hitchcock | Jason Schmidt | Jason Schmidt | Sterling Hitchcock | Jose Silva | 599 | 666 | -67 |
| 1999-09-08 | @ PIT | 140 | W 7-4 | 65-75 | 5 | 10,133 | Woody Williams | Francisco Cordova | Trevor Hoffman | Marc Wilkins | | 606 | 670 | -64 |
| 1999-09-09 | vs MON | 141 | W 10-3 | 65-76 | 5 | 16,676 | Buddy Carlyle | Javier Vazquez | Buddy Carlyle | Javier Vazquez | | 616 | 673 | -57 |
| 1999-09-10 | vs MON | 142 | W 10-3 | 65-77 | 5 | 16,130 | Matt Clement | Jeremy Powell | Matt Clement | Jeremy Powell | | 626 | 676 | -50 |
| 1999-09-11 | vs MON | 143 | L 4-5 | 65-78 | 5 | 55,086 | Andy Ashby | Mike Thurman | Mike Thurman | Andy Ashby | Ugueth Urbina | 630 | 681 | -51 |
| 1999-09-12 | vs MON | 144 | L 4-8 | 65-79 | 5 | 30,870 | Sterling Hitchcock | Dustin Hermanson | Dustin Hermanson | Sterling Hitchcock | Ugueth Urbina | 634 | 689 | -55 |
| 1999-09-13 | vs ATL | 145 | W 3-0 | 66-79 | 5 | 15,718 | Woody Williams | Terry Mulholland | Woody Williams | Terry Mulholland | Trevor Hoffman | 637 | 689 | -52 |
| 1999-09-14 | vs ATL | 146 | L 4-11 | 67-79 | 5 | 18,068 | Buddy Carlyle | Kevin Millwood | Kevin Millwood | Buddy Carlyle | | 641 | 700 | -59 |
| 1999-09-15 | vs ATL | 147 | W 4-1 | 68-79 | 5 | 18,177 | Matt Clement | John Smoltz | Matt Clement | John Smoltz | Trevor Hoffman | 645 | 701 | -56 |
| 1999-09-17 | vs SFN | 148 | L 2-4 | 68-80 | 5 | 29,028 | Andy Ashby | Joe Nathan | Joe Nathan | Andy Ashby | Robb Nen | 647 | 705 | -58 |
| 1999-09-18 | vs SFN | 149 | W 11-5 | 68-81 | 5 | 42,265 | Sterling Hitchcock | Mark Gardner | Sterling Hitchcock | Mark Gardner | | 658 | 710 | -52 |
| 1999-09-19 | vs SFN | 150 | W 6-3 | 69-81 | 5 | 32,443 | Woody Williams | Shawn Estes | Woody Williams | Shawn Estes | Trevor Hoffman | 664 | 713 | -49 |
| 1999-09-20 | vs CIN | 151 | L 1-12 | 69-82 | 5 | 12,837 | Buddy Carlyle | Denny Neagle | Denny Neagle | Buddy Carlyle | | 665 | 725 | -60 |
| 1999-09-21 | vs CIN | 152 | W 6-2 | 70-82 | 5 | 18,512 | Matt Clement | Juan Guzman | Matt Clement | Scott Williamson | | 671 | 727 | -56 |
| 1999-09-22 | vs CIN | 153 | L 3-4 | 70-83 | 5 | 36,788 | Andy Ashby | Ron Villone | Ron Villone | Andy Ashby | Danny Graves | 674 | 731 | -57 |
| 1999-09-24 | @ LAN | 154 | L 1-5 | 70-84 | 5 | 36,366 | Sterling Hitchcock | Kevin Brown | Kevin Brown | Sterling Hitchcock | | 675 | 736 | -61 |
| 1999-09-25 | @ LAN | 155 | W 3-2 | 71-84 | 5 | 41,067 | Woody Williams | Eric Gagne | Woody Williams | Matt Herges | Trevor Hoffman | 678 | 738 | -60 |
| 1999-09-26 | @ LAN | 156 | L 7-10 | 72-84 | 5 | 46,177 | Buddy Carlyle | Jeff Williams | Robinson Checo | Dan Miceli | | 685 | 748 | -63 |
| 1999-09-29 | @ SLN | 157 | L 3-4 | 72-86 | 6 | 0 | Matt Clement | Darren Oliver | Darren Oliver | Donne Wall | Lance Painter | 688 | 752 | -64 |
| 1999-09-29 | @ SLN | 158 | L 5-6 | 72-86 | 6 | 37,049 | Andy Ashby | Jose Jimenez | Juan Acevedo | Domingo Guzman | | 693 | 758 | -65 |
| 1999-09-30 | @ ARI | 159 | L 3-5 | 72-87 | 5 | 33,949 | Sterling Hitchcock | Randy Johnson | Randy Johnson | Sterling Hitchcock | Matt Mantei | 696 | 763 | -67 |
| 1999-10-01 | @ ARI | 160 | W 6-1 | 73-87 | 5 | 38,519 | Woody Williams | Todd Stottlemyre | Woody Williams | Todd Stottlemyre | | 702 | 764 | -62 |
| 1999-10-02 | @ ARI | 161 | L 5-7 | 73-88 | 5 | 46,794 | Buddy Carlyle | Omar Daal | Byung-Hyun Kim | Matt Whisenant | Matt Mantei | 707 | 771 | -64 |
| 1999-10-03 | @ ARI | 162 | L 3-10 | 74-88 | 5 | 43,465 | Heath Murray | Brian Anderson | Brian Anderson | Heath Murray | | 710 | 781 | -71 |