2004 Boston Red Sox season Game log September

| Date_ | Opponent | Score | Loss | Attendance | Record |
|---|---|---|---|---|---|
| September 10 | @ Mariners | 13 - 2 | Franklin (3-15) | 38100 | 85-55 |
| September 11 | @ Mariners | 9 - 0 | Moyer (6-11) | 44401 | 86-55 |
| September 12 | @ Mariners | 2 - 0 | Lowe (14-11) | 43742 | 86-56 |
| September 14 | Devil Rays | 5 - 2 | Martínez (16-6) | 35118 | 86-57 |
| September 15 | Devil Rays | 8 - 6 | Núñez (0-3) | 35105 | 87-57 |
| September 16 | Devil Rays | 11 - 4 | Hendrickson (8-15) | 35048 | 88-57 |
| September 17 | @ Yankees | 3 - 2 | Rivera (4-2) | 55128 | 89-57 |
| September 18 | @ Yankees | 14 - 4 | Lowe (14-12) | 55153 | 89-58 |
| September 19 | @ Yankees | 11 - 1 | Martínez (16-7) | 55142 | 89-59 |
| September 20 | Orioles | 10 - 6 | Wakefield (11-10) | 34758 | 89-60 |