1984 Chicago Cubs season Game log September

| Date_ | Opponent | Score | Loss | Attendance | Record |
|---|---|---|---|---|---|
| September 10 | Phillies | 3 - 2 | Koosman (14-12) | 26083 | 87-57 |
| September 11 | Phillies | 6 - 3 | Smith (9-6) | 28964 | 87-58 |
| September 12 | Expos | 11 - 5 | Smith (11-12) | 20976 | 88-58 |
| September 14 | Mets | 7 - 1 | Darling (12-7) | 32403 | 89-58 |
| September 15 | Mets | 5 - 4 | Fernandez (4-6) | 38653 | 90-58 |
| September 16 | Mets | 9 - 3 | Trout (12-7) | 38936 | 90-59 |
| September 18 | Pirates | 6 - 2 | Eckersley (8-8) | 30721 | 90-60 |
| September 19 | Pirates | 11 - 6 | Stoddard (10-6) | 31585 | 90-61 |
| September 20 | Pirates | 7 - 6 | Smith (9-7) | 33651 | 90-62 |
| September 21 | @ Cardinals | 8 - 0 | Sanderson (8-5) | 36847 | 90-63 |