| 1989-04-03 | @ BAL | 1 | L 4-5 | 0-1 | 4 | 52,161 | Roger Clemens | Dave J. Schmidt | Brian Holton | Bob Stanley | | 4 | 5 | -1 |
| 1989-04-06 | @ BAL | 2 | L 4-6 | 0-2 | 6 | 22,041 | Mike Boddicker | Jose Bautista | Jose Bautista | Mike Smithson | Mark Williamson | 8 | 11 | -3 |
| 1989-04-07 | @ KCA | 3 | L 8-9 | 0-3 | 7 | 21,770 | Oil Can Boyd | Floyd Bannister | Jeff Montgomery | Lee Smith | | 16 | 20 | -4 |
| 1989-04-08 | @ KCA | 4 | L 1-2 | 0-4 | 7 | 28,266 | Roger Clemens | Mark Gubicza | Luis Aquino | Rob Murphy | | 17 | 22 | -5 |
| 1989-04-09 | @ KCA | 5 | W 8-6 | 1-4 | 6 | 25,637 | Wes Gardner | Charlie Leibrandt | John Dopson | Jeff Montgomery | Mike Smithson | 25 | 28 | -3 |
| 1989-04-10 | vs CLE | 6 | W 5-2 | 2-4 | 5 | 32,909 | Mike Boddicker | Joe Skalski | Mike Boddicker | Joe Skalski | Mike Smithson | 30 | 30 | 0 |
| 1989-04-12 | vs CLE | 7 | L 6-10 | 2-5 | 5 | 19,210 | Oil Can Boyd | Buddy Black | Buddy Black | Oil Can Boyd | Keith Atherton | 36 | 40 | -4 |
| 1989-04-13 | vs CLE | 8 | W 9-1 | 3-5 | 4 | 18,518 | Roger Clemens | Rich Yett | Roger Clemens | Rich Yett | | 45 | 41 | 4 |
| 1989-04-14 | vs BAL | 9 | W 7-4 | 4-5 | 4 | 24,460 | John Dopson | Dave J. Schmidt | John Dopson | Dave J. Schmidt | Bob Stanley | 52 | 45 | 7 |
| 1989-04-15 | vs BAL | 10 | L 4-12 | 4-6 | 5 | 28,457 | Mike Boddicker | Jeff Ballard | Jeff Ballard | Mike Boddicker | Gregg Olson | 56 | 57 | -1 |
| 1989-04-17 | vs BAL | 11 | W 6-4 | 5-6 | 4 | 32,923 | Wes Gardner | Jose Bautista | Lee Smith | Brian Holton | Bob Stanley | 62 | 61 | 1 |
| 1989-04-19 | @ CLE | 12 | W 8-4 | 6-6 | 1 | 6,182 | Roger Clemens | Buddy Black | Roger Clemens | Buddy Black | | 70 | 65 | 5 |
| 1989-04-20 | @ CLE | 13 | W 5-2 | 7-6 | 1 | 7,236 | Oil Can Boyd | Rich Yett | Oil Can Boyd | Rich Yett | Lee Smith | 75 | 67 | 8 |
| 1989-04-21 | vs KCA | 14 | L 4-7 | 7-7 | 1 | 31,766 | John Dopson | Floyd Bannister | Floyd Bannister | John Dopson | | 79 | 74 | 5 |
| 1989-04-22 | vs KCA | 15 | L 3-7 | 7-8 | 3 | 33,048 | Mike Boddicker | Mark Gubicza | Mark Gubicza | Mike Boddicker | | 82 | 81 | 1 |
| 1989-04-23 | vs KCA | 16 | L 0-10 | 7-9 | 3 | 33,116 | Wes Gardner | Charlie Leibrandt | Charlie Leibrandt | Wes Gardner | | 82 | 91 | -9 |
| 1989-04-25 | vs CHA | 17 | W 11-0 | 8-9 | 3 | 21,326 | Roger Clemens | Melido Perez | Roger Clemens | Melido Perez | | 93 | 91 | 2 |
| 1989-04-26 | vs CHA | 18 | W 5-4 | 9-9 | 3 | 22,948 | Oil Can Boyd | Jerry Reuss | Bob Stanley | Barry Jones | | 98 | 95 | 3 |
| 1989-04-27 | vs CHA | 19 | L 1-3 | 9-10 | 3 | 23,830 | John Dopson | Eric King | Donn Pall | Mike Smithson | | 99 | 98 | 1 |
| 1989-04-28 | @ TEX | 20 | L 6-7 | 9-11 | 4 | 35,440 | Mike Boddicker | Kevin Brown | Cecilio Guante | Rob Murphy | | 105 | 105 | 0 |
| 1989-04-29 | @ TEX | 21 | W 8-5 | 10-11 | 3 | 41,050 | Wes Gardner | Charlie Hough | Wes Gardner | Charlie Hough | Lee Smith | 113 | 110 | 3 |
| 1989-04-30 | @ TEX | 22 | L 1-2 | 10-12 | 3 | 40,429 | Roger Clemens | Nolan Ryan | Nolan Ryan | Roger Clemens | Jeff Russell | 114 | 112 | 2 |
| 1989-05-01 | @ MIN | 23 | W 13-6 | 11-12 | 3 | 18,347 | Oil Can Boyd | Allan Anderson | Oil Can Boyd | Allan Anderson | | 127 | 118 | 9 |
| 1989-05-02 | @ MIN | 24 | W 4-2 | 12-12 | 2 | 17,765 | John Dopson | Freddie Toliver | John Dopson | German Gonzalez | Lee Smith | 131 | 120 | 11 |
| 1989-05-03 | @ CHA | 25 | W 8-4 | 13-12 | 1 | 8,688 | Mike Boddicker | Shawn Hillegas | Mike Boddicker | Shawn Hillegas | Bob Stanley | 139 | 124 | 15 |
| 1989-05-04 | @ CHA | 26 | L 4-5 | 13-13 | 2 | 7,443 | Wes Gardner | Bill Long | Bill Long | Wes Gardner | Bobby Thigpen | 143 | 129 | 14 |
| 1989-05-05 | vs TEX | 27 | W 7-6 | 14-13 | 1 | 32,555 | Roger Clemens | Nolan Ryan | Roger Clemens | Nolan Ryan | Bob Stanley | 150 | 135 | 15 |
| 1989-05-06 | vs TEX | 28 | W 7-0 | 15-13 | 1 | 31,508 | Mike Smithson | Bobby Witt | Mike Smithson | Bobby Witt | | 157 | 135 | 22 |
| 1989-05-07 | vs TEX | 29 | W 9-5 | 16-13 | 1 | 33,067 | John Dopson | Jamie Moyer | John Dopson | Jamie Moyer | Lee Smith | 166 | 140 | 26 |
| 1989-05-08 | vs MIN | 30 | L 2-4 | 16-14 | 1 | 23,618 | Mike Boddicker | Shane Rawley | Shane Rawley | Mike Boddicker | Jeff Reardon | 168 | 144 | 24 |
| 1989-05-09 | vs MIN | 31 | L 2-6 | 16-15 | 1 | 25,951 | Wes Gardner | Frank Viola | Frank Viola | Wes Gardner | Jeff Reardon | 170 | 150 | 20 |
| 1989-05-12 | @ SEA | 32 | W 2-0 | 17-15 | 1 | 25,239 | Roger Clemens | Scott Bankhead | Roger Clemens | Scott Bankhead | | 172 | 150 | 22 |
| 1989-05-13 | @ SEA | 33 | L 6-14 | 17-16 | 1 | 29,689 | John Dopson | Bill Swift | Jerry Reed | John Dopson | | 178 | 164 | 14 |
| 1989-05-14 | @ SEA | 34 | L 3-4 | 17-17 | 1 | 13,618 | Mike Boddicker | Erik Hanson | Steve Trout | Mike Boddicker | Mike Schooler | 181 | 168 | 13 |
| 1989-05-16 | @ CAL | 35 | L 2-7 | 17-18 | 2 | 26,043 | Mike Smithson | Kirk McCaskill | Kirk McCaskill | Mike Smithson | | 183 | 175 | 8 |
| 1989-05-17 | @ CAL | 36 | L 0-5 | 17-19 | 3 | 31,230 | Roger Clemens | Jim Abbott | Jim Abbott | Roger Clemens | | 183 | 180 | 3 |
| 1989-05-18 | @ CAL | 37 | W 5-2 | 18-19 | 1 | 28,114 | John Dopson | Mike Witt | John Dopson | Mike Witt | Rob Murphy | 188 | 182 | 6 |
| 1989-05-19 | @ OAK | 38 | W 7-4 | 19-19 | 1 | 40,382 | Mike Boddicker | Mike Moore | Bob Stanley | Gene Nelson | | 195 | 186 | 9 |
| 1989-05-20 | @ OAK | 39 | L 3-6 | 19-20 | 1 | 43,427 | Wes Gardner | Dave Stewart | Dave Stewart | Wes Gardner | Dennis Eckersley | 198 | 192 | 6 |
| 1989-05-21 | @ OAK | 40 | L 4-5 | 19-21 | 3 | 44,505 | Roger Clemens | Curt Young | Todd Burns | Roger Clemens | Dennis Eckersley | 202 | 197 | 5 |
| 1989-05-23 | vs SEA | 41 | W 6-5 | 20-21 | 3 | 28,069 | John Dopson | Bill Swift | Lee Smith | Jerry Reed | | 208 | 202 | 6 |
| 1989-05-24 | vs SEA | 42 | W 6-5 | 21-21 | 2 | 23,784 | Mike Boddicker | Erik Hanson | Mike Boddicker | Erik Hanson | Lee Smith | 214 | 207 | 7 |
| 1989-05-25 | vs SEA | 43 | W 10-0 | 22-21 | 1 | 26,335 | Mike Smithson | Mike Dunne | Mike Smithson | Mike Dunne | | 224 | 207 | 17 |
| 1989-05-26 | vs CAL | 44 | L 0-5 | 22-22 | 2 | 32,417 | Roger Clemens | Chuck Finley | Chuck Finley | Roger Clemens | | 224 | 212 | 12 |
| 1989-05-28 | vs CAL | 45 | L 0-3 | 22-23 | 2 | 34,311 | John Dopson | Kirk McCaskill | Kirk McCaskill | John Dopson | | 224 | 215 | 9 |
| 1989-05-29 | vs OAK | 46 | W 3-2 | 23-23 | 2 | 33,344 | Mike Boddicker | Bob Welch | Lee Smith | Bob Welch | | 227 | 217 | 10 |
| 1989-05-30 | vs OAK | 47 | L 2-4 | 23-24 | 2 | 31,407 | Mike Smithson | Dave Stewart | Dave Stewart | Mike Smithson | Rick Honeycutt | 229 | 221 | 8 |
| 1989-05-31 | vs OAK | 48 | W 4-3 | 24-24 | 2 | 33,510 | Roger Clemens | Todd Burns | Lee Smith | Eric Plunk | | 233 | 224 | 9 |
| 1989-06-02 | vs TOR | 49 | L 2-7 | 24-25 | 3 | 33,584 | John Dopson | John Cerutti | John Cerutti | John Dopson | Duane Ward | 235 | 231 | 4 |
| 1989-06-03 | vs TOR | 50 | L 2-10 | 24-26 | 3 | 33,942 | Mike Boddicker | Dave Stieb | Dave Stieb | Mike Boddicker | | 237 | 241 | -4 |
| 1989-06-04 | vs TOR | 51 | L 11-13 | 24-27 | 3 | 33,760 | Mike Smithson | Alex Sanchez | Duane Ward | Dennis Lamp | | 248 | 254 | -6 |
| 1989-06-05 | @ DET | 52 | W 5-2 | 25-27 | 3 | 20,722 | Roger Clemens | David Palmer | Roger Clemens | David Palmer | Rob Murphy | 253 | 256 | -3 |
| 1989-06-06 | @ DET | 53 | L 1-5 | 25-28 | 3 | 16,387 | Joe Price | Mike Schwabe | Mike Schwabe | Joe Price | Guillermo Hernandez | 254 | 261 | -7 |
| 1989-06-07 | @ DET | 54 | W 6-1 | 26-28 | 3 | 17,741 | John Dopson | Doyle Alexander | John Dopson | Doyle Alexander | | 260 | 262 | -2 |
| 1989-06-08 | @ NYA | 55 | L 7-8 | 26-29 | 4 | 28,329 | Mike Boddicker | Clay Parker | Lance McCullers | Bob Stanley | | 267 | 270 | -3 |
| 1989-06-10 | @ NYA | 56 | W 14-8 | 27-29 | 3 | 49,348 | Roger Clemens | Richard Dotson | Roger Clemens | Richard Dotson | | 281 | 278 | 3 |
| 1989-06-11 | @ NYA | 57 | L 2-4 | 27-31 | 5 | 0 | Joe Price | Andy Hawkins | Andy Hawkins | Joe Price | Dave Righetti | 283 | 282 | 1 |
| 1989-06-11 | @ NYA | 58 | L 7-8 | 27-31 | 5 | 54,525 | Mike Smithson | Jimmy Jones | Scott Nielsen | Rob Murphy | Lee Guetterman | 290 | 290 | 0 |
| 1989-06-13 | vs DET | 59 | W 8-7 | 28-31 | 4 | 30,969 | John Dopson | David Palmer | Wes Gardner | Frank Williams | Lee Smith | 298 | 297 | 1 |
| 1989-06-14 | vs DET | 60 | L 3-7 | 28-32 | 4 | 32,656 | Mike Boddicker | Frank Tanana | Frank Tanana | Mike Boddicker | | 301 | 304 | -3 |
| 1989-06-16 | @ CHA | 61 | W 2-0 | 29-32 | 5 | 16,898 | Roger Clemens | Greg Hibbard | Roger Clemens | Ken Patterson | | 303 | 304 | -1 |
| 1989-06-17 | @ CHA | 62 | W 6-1 | 30-32 | 4 | 25,258 | Mike Smithson | Melido Perez | Mike Smithson | Melido Perez | | 309 | 305 | 4 |
| 1989-06-18 | @ CHA | 63 | W 7-4 | 31-32 | 4 | 16,350 | Joe Price | Steve Rosenberg | Joe Price | Steve Rosenberg | Lee Smith | 316 | 309 | 7 |
| 1989-06-19 | @ CHA | 64 | L 2-8 | 31-33 | 4 | 12,712 | John Dopson | Adam Peterson | Shawn Hillegas | John Dopson | Donn Pall | 318 | 317 | 1 |
| 1989-06-20 | vs TEX | 65 | W 6-3 | 32-33 | 2 | 34,443 | Mike Boddicker | Nolan Ryan | Mike Boddicker | Jeff Russell | Lee Smith | 324 | 320 | 4 |
| 1989-06-21 | vs TEX | 66 | L 3-10 | 32-34 | 3 | 34,338 | Roger Clemens | Bobby Witt | Gary Mielke | Roger Clemens | | 327 | 330 | -3 |
| 1989-06-22 | vs TEX | 67 | L 1-9 | 32-35 | 4 | 34,000 | Mike Smithson | Kevin Brown | Kevin Brown | Mike Smithson | | 328 | 339 | -11 |
| 1989-06-23 | vs MIN | 68 | L 0-10 | 32-36 | 4 | 33,548 | Joe Price | Frank Viola | Frank Viola | Joe Price | | 328 | 349 | -21 |
| 1989-06-24 | vs MIN | 69 | W 6-2 | 34-36 | 4 | 33,346 | John Dopson | Francisco Oliveras | John Dopson | Francisco Oliveras | | 334 | 351 | -17 |
| 1989-06-24 | vs MIN | 70 | W 11-2 | 34-36 | 4 | 18,819 | Wes Gardner | Freddie Toliver | Mike Smithson | Freddie Toliver | | 345 | 353 | -8 |
| 1989-06-25 | vs MIN | 71 | L 0-7 | 34-37 | 4 | 34,007 | Mike Boddicker | Allan Anderson | Allan Anderson | Mike Boddicker | | 345 | 360 | -15 |
| 1989-06-27 | @ MIL | 72 | L 4-5 | 34-38 | 5 | 17,541 | Roger Clemens | Don August | Don August | Roger Clemens | Dan Plesac | 349 | 365 | -16 |
| 1989-06-28 | @ MIL | 73 | L 5-12 | 34-39 | 6 | 18,813 | Mike Smithson | Teddy Higuera | Teddy Higuera | Mike Smithson | | 354 | 377 | -23 |
| 1989-06-29 | @ MIL | 74 | W 2-1 | 35-39 | 6 | 31,202 | John Dopson | Chris Bosio | John Dopson | Chris Bosio | Lee Smith | 356 | 378 | -22 |
| 1989-06-30 | @ TOR | 75 | W 3-1 | 36-39 | 3 | 48,429 | Mike Boddicker | Jimmy Key | Mike Boddicker | David Wells | Rob Murphy | 359 | 379 | -20 |
| 1989-07-01 | @ TOR | 76 | W 3-1 | 37-39 | 3 | 48,639 | Eric Hetzel | Todd Stottlemyre | Eric Hetzel | Todd Stottlemyre | Lee Smith | 362 | 380 | -18 |
| 1989-07-02 | @ TOR | 77 | W 4-1 | 38-39 | 3 | 48,516 | Roger Clemens | Mike Flanagan | Rob Murphy | David Wells | Lee Smith | 366 | 381 | -15 |
| 1989-07-03 | @ TOR | 78 | L 2-3 | 38-40 | 3 | 48,483 | Mike Smithson | John Cerutti | John Cerutti | Mike Smithson | Duane Ward | 368 | 384 | -16 |
| 1989-07-04 | vs MIL | 79 | L 3-4 | 38-41 | 4 | 26,120 | John Dopson | Chris Bosio | Chris Bosio | Joe Price | Dan Plesac | 371 | 388 | -17 |
| 1989-07-06 | vs MIL | 80 | W 5-4 | 39-41 | 3 | 33,538 | Mike Boddicker | Jaime Navarro | Mike Boddicker | Jaime Navarro | Lee Smith | 376 | 392 | -16 |
| 1989-07-07 | vs NYA | 81 | W 6-4 | 40-41 | 3 | 33,368 | Roger Clemens | Greg Cadaret | Roger Clemens | Greg Cadaret | Rob Murphy | 382 | 396 | -14 |
| 1989-07-08 | vs NYA | 82 | L 5-7 | 40-42 | 3 | 33,923 | Eric Hetzel | Dave Eiland | Eric Plunk | Mike Smithson | Dave Righetti | 387 | 403 | -16 |
| 1989-07-09 | vs NYA | 83 | W 10-5 | 41-42 | 3 | 33,521 | John Dopson | Don Schulze | Lee Smith | Don Schulze | | 397 | 408 | -11 |
| 1989-07-13 | @ MIN | 84 | W 3-1 | 42-42 | 3 | 30,899 | Roger Clemens | Frank Viola | Roger Clemens | Frank Viola | Lee Smith | 400 | 409 | -9 |
| 1989-07-14 | @ MIN | 85 | W 5-0 | 43-42 | 2 | 27,621 | Mike Boddicker | Allan Anderson | Mike Boddicker | Allan Anderson | | 405 | 409 | -4 |
| 1989-07-15 | @ MIN | 86 | L 2-3 | 43-43 | 2 | 33,239 | Eric Hetzel | Roy Smith | Juan Berenguer | Mike Smithson | Jeff Reardon | 407 | 412 | -5 |
| 1989-07-16 | @ MIN | 87 | L 3-4 | 43-44 | 3 | 40,593 | John Dopson | Shane Rawley | Randy St. Claire | Rob Murphy | | 410 | 416 | -6 |
| 1989-07-17 | @ TEX | 88 | L 6-12 | 43-45 | 4 | 27,230 | Wes Gardner | Mike Jeffcoat | Cecilio Guante | Wes Gardner | | 416 | 428 | -12 |
| 1989-07-18 | @ TEX | 89 | L 1-8 | 43-46 | 4 | 30,275 | Roger Clemens | Bobby Witt | Bobby Witt | Roger Clemens | | 417 | 436 | -19 |
| 1989-07-19 | @ TEX | 90 | W 4-0 | 44-46 | 4 | 22,830 | Mike Boddicker | Charlie Hough | Mike Boddicker | Charlie Hough | Rob Murphy | 421 | 436 | -15 |
| 1989-07-21 | vs CHA | 91 | L 0-1 | 44-47 | 4 | 34,925 | Eric Hetzel | Melido Perez | Melido Perez | Eric Hetzel | Bobby Thigpen | 421 | 437 | -16 |
| 1989-07-22 | vs CHA | 92 | L 6-10 | 44-48 | 5 | 34,899 | John Dopson | Richard Dotson | Ken Patterson | Rob Murphy | Donn Pall | 427 | 447 | -20 |
| 1989-07-23 | vs CHA | 93 | W 8-2 | 45-48 | 4 | 34,519 | Roger Clemens | Steve Rosenberg | Roger Clemens | Steve Rosenberg | | 435 | 449 | -14 |
| 1989-07-25 | vs KCA | 94 | W 10-0 | 46-48 | 4 | 34,944 | Mike Boddicker | Charlie Leibrandt | Mike Boddicker | Charlie Leibrandt | | 445 | 449 | -4 |
| 1989-07-26 | vs KCA | 95 | L 4-7 | 46-49 | 4 | 34,681 | Eric Hetzel | Bret Saberhagen | Bret Saberhagen | Joe Price | Jeff Montgomery | 449 | 456 | -7 |
| 1989-07-27 | vs KCA | 96 | W 7-2 | 47-49 | 4 | 34,223 | John Dopson | Tom Gordon | John Dopson | Tom Gordon | | 456 | 458 | -2 |
| 1989-07-28 | @ CLE | 97 | L 2-3 | 47-51 | 5 | 0 | Roger Clemens | Tom Candiotti | Tom Candiotti | Roger Clemens | | 458 | 461 | -3 |
| 1989-07-28 | @ CLE | 98 | L 1-2 | 47-51 | 5 | 35,792 | Wes Gardner | Rod Nichols | Rod Nichols | Wes Gardner | Doug Jones | 459 | 463 | -4 |
| 1989-07-29 | @ CLE | 99 | W 5-0 | 48-51 | 5 | 26,146 | Mike Smithson | Buddy Black | Mike Smithson | Buddy Black | | 464 | 463 | 1 |
| 1989-07-30 | @ CLE | 100 | W 5-2 | 49-51 | 4 | 25,022 | Mike Boddicker | John Farrell | Dennis Lamp | John Farrell | Rob Murphy | 469 | 465 | 4 |
| 1989-07-31 | vs BAL | 101 | W 9-6 | 50-51 | 3 | 33,826 | Eric Hetzel | Bob Milacki | Bob Stanley | Bob Milacki | Lee Smith | 478 | 471 | 7 |
| 1989-08-01 | vs BAL | 102 | W 5-3 | 52-51 | 2 | 35,111 | John Dopson | Pete Harnisch | Rob Murphy | Pete Harnisch | Lee Smith | 483 | 474 | 9 |
| 1989-08-01 | vs BAL | 103 | W 6-2 | 52-51 | 2 | 34,901 | Wes Gardner | Dave Johnson | Wes Gardner | Dave Johnson | | 489 | 476 | 13 |
| 1989-08-02 | vs BAL | 104 | L 8-9 | 52-52 | 2 | 34,970 | Joe Price | Jeff Ballard | Mark Williamson | Eric Hetzel | Mark Thurmond | 497 | 485 | 12 |
| 1989-08-03 | vs CLE | 105 | L 2-4 | 52-53 | 3 | 33,992 | Tom Bolton | Rod Nichols | Rod Nichols | Tom Bolton | Doug Jones | 499 | 489 | 10 |
| 1989-08-04 | vs CLE | 106 | L 3-4 | 52-54 | 4 | 34,154 | Mike Boddicker | Buddy Black | Buddy Black | Mike Boddicker | Doug Jones | 502 | 493 | 9 |
| 1989-08-05 | vs CLE | 107 | W 10-2 | 53-54 | 3 | 34,090 | Mike Smithson | John Farrell | Mike Smithson | John Farrell | | 512 | 495 | 17 |
| 1989-08-06 | vs CLE | 108 | W 6-4 | 54-54 | 2 | 33,935 | Roger Clemens | Ed Wojna | Rob Murphy | Jesse Orosco | | 518 | 499 | 19 |
| 1989-08-07 | @ KCA | 109 | L 4-6 | 54-55 | 3 | 40,803 | Wes Gardner | Mark Gubicza | Mark Gubicza | Greg Harris | Steve Farr | 522 | 505 | 17 |
| 1989-08-08 | @ KCA | 110 | L 1-8 | 54-56 | 4 | 32,015 | Tom Bolton | Tom Gordon | Tom Gordon | Tom Bolton | | 523 | 513 | 10 |
| 1989-08-09 | @ KCA | 111 | W 6-2 | 55-56 | 4 | 37,225 | Mike Boddicker | Luis Aquino | Mike Boddicker | Luis Aquino | | 529 | 515 | 14 |
| 1989-08-11 | @ BAL | 112 | W 6-4 | 56-57 | 3 | 0 | Roger Clemens | Bob Milacki | Roger Clemens | Bob Milacki | | 535 | 519 | 16 |
| 1989-08-11 | @ BAL | 113 | L 1-4 | 56-57 | 3 | 49,003 | Mike Smithson | Pete Harnisch | Pete Harnisch | Mike Smithson | | 536 | 523 | 13 |
| 1989-08-12 | @ BAL | 114 | W 10-8 | 57-57 | 2 | 50,865 | Wes Gardner | Jeff Ballard | Bob Stanley | Kevin Hickey | | 546 | 531 | 15 |
| 1989-08-13 | @ BAL | 115 | L 1-6 | 57-58 | 3 | 46,335 | Tom Bolton | Dave Johnson | Dave Johnson | Tom Bolton | | 547 | 537 | 10 |
| 1989-08-14 | vs TOR | 116 | L 2-4 | 57-59 | 4 | 35,058 | Mike Boddicker | Mauro Gozzo | Mauro Gozzo | Mike Boddicker | Tom Henke | 549 | 541 | 8 |
| 1989-08-15 | vs TOR | 117 | L 2-7 | 57-60 | 4 | 34,800 | Mike Smithson | Dave Stieb | Dave Stieb | Mike Smithson | Duane Ward | 551 | 548 | 3 |
| 1989-08-16 | vs TOR | 118 | L 3-7 | 57-61 | 5 | 35,310 | Roger Clemens | Todd Stottlemyre | David Wells | Rob Murphy | Tom Henke | 554 | 555 | -1 |
| 1989-08-17 | @ MIL | 119 | L 4-8 | 57-62 | 5 | 33,978 | Wes Gardner | Chris Bosio | Chris Bosio | Wes Gardner | | 558 | 563 | -5 |
| 1989-08-18 | @ MIL | 120 | L 2-5 | 57-63 | 5 | 42,215 | Tom Bolton | Tom Filer | Tom Filer | Tom Bolton | Bill Krueger | 560 | 568 | -8 |
| 1989-08-19 | @ MIL | 121 | W 3-1 | 58-63 | 4 | 49,539 | Mike Boddicker | Jeff Peterek | Greg Harris | Mark Knudson | | 563 | 569 | -6 |
| 1989-08-20 | @ MIL | 122 | L 3-6 | 58-64 | 4 | 45,579 | Mike Smithson | Teddy Higuera | Jaime Navarro | Mike Smithson | Tony Fossas | 566 | 575 | -9 |
| 1989-08-21 | @ NYA | 123 | L 4-6 | 58-65 | 4 | 33,059 | Roger Clemens | Walt Terrell | Walt Terrell | Roger Clemens | Rich Gossage | 570 | 581 | -11 |
| 1989-08-22 | @ NYA | 124 | W 4-3 | 59-65 | 4 | 33,514 | Wes Gardner | Greg Cadaret | Rob Murphy | John Candelaria | Lee Smith | 574 | 584 | -10 |
| 1989-08-23 | @ NYA | 125 | W 4-1 | 60-65 | 4 | 33,663 | Mike Boddicker | Andy Hawkins | Mike Boddicker | Andy Hawkins | Lee Smith | 578 | 585 | -7 |
| 1989-08-25 | vs DET | 126 | W 4-2 | 62-65 | 4 | 0 | Mike Smithson | Doyle Alexander | Mike Smithson | Doyle Alexander | Rob Murphy | 582 | 587 | -5 |
| 1989-08-25 | vs DET | 127 | W 11-3 | 62-65 | 4 | 35,158 | Eric Hetzel | Kevin Ritz | Dennis Lamp | Kevin Ritz | | 593 | 590 | 3 |
| 1989-08-26 | vs DET | 128 | W 5-2 | 63-65 | 4 | 34,643 | Roger Clemens | Frank Tanana | Roger Clemens | Frank Tanana | Lee Smith | 598 | 592 | 6 |
| 1989-08-27 | vs DET | 129 | W 7-1 | 64-65 | 3 | 34,252 | Wes Gardner | Brian Dubois | Joe Price | Brian Dubois | | 605 | 593 | 12 |
| 1989-08-28 | vs DET | 130 | W 6-3 | 65-65 | 3 | 33,307 | Mike Boddicker | Jeff Robinson | Mike Boddicker | Jeff Robinson | Lee Smith | 611 | 596 | 15 |
| 1989-08-29 | vs CAL | 131 | W 8-4 | 67-65 | 3 | 0 | Mike Smithson | Bert Blyleven | Dennis Lamp | Bert Blyleven | | 619 | 600 | 19 |
| 1989-08-29 | vs CAL | 132 | W 13-5 | 67-65 | 3 | 33,987 | Eric Hetzel | Dan Petry | Bob Stanley | Dan Petry | | 632 | 605 | 27 |
| 1989-08-30 | vs CAL | 133 | L 0-4 | 67-66 | 3 | 34,182 | John Dopson | Jim Abbott | Jim Abbott | John Dopson | | 632 | 609 | 23 |
| 1989-08-31 | vs CAL | 134 | W 5-2 | 68-66 | 3 | 31,737 | Roger Clemens | Kirk McCaskill | Roger Clemens | Kirk McCaskill | | 637 | 611 | 26 |
| 1989-09-01 | vs SEA | 135 | L 2-7 | 68-67 | 3 | 31,581 | Mike Smithson | Scott Bankhead | Scott Bankhead | Mike Smithson | Michael Jackson | 639 | 618 | 21 |
| 1989-09-02 | vs SEA | 136 | W 6-5 | 69-67 | 3 | 33,615 | Mike Boddicker | Mike Dunne | Dennis Lamp | Mike Dunne | Lee Smith | 645 | 623 | 22 |
| 1989-09-03 | vs SEA | 137 | L 2-3 | 69-68 | 3 | 35,035 | Oil Can Boyd | Erik Hanson | Erik Hanson | Oil Can Boyd | Mike Schooler | 647 | 626 | 21 |
| 1989-09-04 | @ OAK | 138 | W 8-5 | 70-68 | 3 | 32,697 | John Dopson | Mike Moore | John Dopson | Mike Moore | Lee Smith | 655 | 631 | 24 |
| 1989-09-05 | @ OAK | 139 | L 1-13 | 70-69 | 3 | 28,541 | Roger Clemens | Curt Young | Curt Young | Roger Clemens | | 656 | 644 | 12 |
| 1989-09-06 | @ OAK | 140 | L 5-7 | 70-70 | 3 | 25,037 | Mike Smithson | Bob Welch | Bob Welch | Mike Smithson | Dennis Eckersley | 661 | 651 | 10 |
| 1989-09-08 | @ CAL | 141 | L 1-2 | 70-71 | 3 | 32,408 | Mike Boddicker | Bert Blyleven | Bert Blyleven | Mike Boddicker | Bryan Harvey | 662 | 653 | 9 |
| 1989-09-09 | @ CAL | 142 | L 5-8 | 70-72 | 4 | 42,033 | Oil Can Boyd | Jim Abbott | Willie Fraser | Rob Murphy | Bryan Harvey | 667 | 661 | 6 |
| 1989-09-10 | @ CAL | 143 | L 1-2 | 70-73 | 4 | 37,980 | Roger Clemens | Kirk McCaskill | Bob McClure | Dennis Lamp | | 668 | 663 | 5 |
| 1989-09-11 | @ SEA | 144 | L 1-2 | 70-74 | 4 | 14,567 | John Dopson | Brian Holman | Brian Holman | John Dopson | Mike Schooler | 669 | 665 | 4 |
| 1989-09-12 | @ SEA | 145 | L 3-5 | 70-75 | 4 | 9,690 | Eric Hetzel | Scott Bankhead | Scott Bankhead | Eric Hetzel | Mike Schooler | 672 | 670 | 2 |
| 1989-09-13 | @ SEA | 146 | L 4-7 | 70-76 | 4 | 8,837 | Mike Boddicker | Clint Zavaras | Jerry Reed | Mike Boddicker | Mike Schooler | 676 | 677 | -1 |
| 1989-09-15 | vs OAK | 147 | W 7-2 | 71-76 | 4 | 33,533 | Roger Clemens | Mike Moore | Roger Clemens | Mike Moore | | 683 | 679 | 4 |
| 1989-09-16 | vs OAK | 148 | W 5-2 | 72-76 | 4 | 33,778 | John Dopson | Storm Davis | John Dopson | Storm Davis | Dennis Lamp | 688 | 681 | 7 |
| 1989-09-17 | vs OAK | 149 | W 7-6 | 73-76 | 4 | 33,148 | Eric Hetzel | Bob Welch | Greg Harris | Bob Welch | Lee Smith | 695 | 687 | 8 |
| 1989-09-18 | @ TOR | 150 | W 6-3 | 74-76 | 4 | 49,579 | Mike Boddicker | John Cerutti | Mike Boddicker | John Cerutti | Rob Murphy | 701 | 690 | 11 |
| 1989-09-19 | @ TOR | 151 | L 5-6 | 74-77 | 4 | 49,352 | Oil Can Boyd | Mike Flanagan | Tom Henke | Greg Harris | | 706 | 696 | 10 |
| 1989-09-20 | @ TOR | 152 | W 10-3 | 75-77 | 4 | 49,571 | Roger Clemens | Jimmy Key | Roger Clemens | Jimmy Key | | 716 | 699 | 17 |
| 1989-09-22 | @ DET | 153 | W 9-7 | 76-77 | 4 | 16,341 | John Dopson | Doyle Alexander | Rob Murphy | Ed Nunez | Lee Smith | 725 | 706 | 19 |
| 1989-09-23 | @ DET | 154 | W 6-1 | 77-77 | 4 | 22,783 | Mike Boddicker | Kevin Ritz | Mike Boddicker | Kevin Ritz | Rob Murphy | 731 | 707 | 24 |
| 1989-09-24 | @ DET | 155 | W 4-2 | 78-77 | 4 | 16,601 | Oil Can Boyd | Jack Morris | Oil Can Boyd | Jack Morris | Lee Smith | 735 | 709 | 26 |
| 1989-09-25 | vs NYA | 156 | W 7-4 | 79-77 | 3 | 32,759 | Roger Clemens | Kevin Mmahat | Roger Clemens | Kevin Mmahat | Lee Smith | 742 | 713 | 29 |
| 1989-09-26 | vs NYA | 157 | W 9-5 | 80-77 | 3 | 31,932 | Eric Hetzel | Andy Hawkins | Eric Hetzel | Andy Hawkins | | 751 | 718 | 33 |
| 1989-09-27 | vs NYA | 158 | L 0-3 | 80-78 | 3 | 32,685 | John Dopson | Walt Terrell | Walt Terrell | John Dopson | | 751 | 721 | 30 |
| 1989-09-28 | vs MIL | 159 | W 12-6 | 81-78 | 3 | 28,954 | Mike Boddicker | Don August | Mike Boddicker | Don August | | 763 | 727 | 36 |
| 1989-09-29 | vs MIL | 160 | W 5-4 | 82-78 | 3 | 32,906 | Oil Can Boyd | Tom Filer | Lee Smith | Chuck Crim | | 768 | 731 | 37 |
| 1989-09-30 | vs MIL | 161 | L 1-3 | 82-79 | 3 | 33,243 | Roger Clemens | Mark Knudson | Mark Knudson | Roger Clemens | Dan Plesac | 769 | 734 | 35 |
| 1989-10-01 | vs MIL | 162 | W 5-1 | 83-79 | 3 | 33,027 | John Dopson | Jaime Navarro | John Dopson | Jaime Navarro | Dennis Lamp | 774 | 735 | 39 |