Fun September Fact: In 1979, the Mets played 32 games in September. Thirty-two miserable 1979 Mets baseball games.
* While regular-season games played in October are sort of generally treated as "September baseball," this survey only includes games actually played in the calendar month.
| Day | Date | Opp. | Starter | Opp. Starter | Score | Div. GB | WC1 GB | WC2 GB | WC3 GB |
|---|---|---|---|---|---|---|---|---|---|
| Sunday | 1 | @CWS | Sean Manaea (L) | Garrett Crochet (L) | W, 2–0 | 8.0 | 4.0 | 4.0 | 1.0 |
| Monday | 2 | vs. BOS | Luís Severino (R) | Brayan Bello (R) | W, 4–1 | 7.5 | 4.0 | 3.0 | 0.5 |
| Tuesday | 3 | vs. BOS | David Peterson (L) | Kutter Crawford (R) | W, 7–2 | 7.5 | 3.5 | 3.0 | 0.5 |
| Wednesday | 4 | vs. BOS | Tylor Megill (R) | Tanner Houck (R) | W, 8–3 | 7.5 | 3.5 | 3.0 | 0.5 |
| Thursday | 5 | 8.0 | 3.0 | 2.5 | 0.0 | ||||
| Friday | 6 | vs. CIN | Sean Manaea (L) | Brandon Williamson (L) | W, 6–4 | 8.0 | 3.0 | 1.5 | 0.0 |
| Saturday | 7 | vs. CIN | José Quintana (L) | Jakob Junis (R) | W, 4-0 | 7.0 | 2.0 | 0.5 | +1.0 |
| Sunday | 8 | vs. CIN | Luís Severino (R) | Julian Aguilar (R) | L, 3-1 | 7.0 | 2.0 | 1.5 | 0.0 |
| SQUEAKY | BUM | TIME | 🐭 | ( | ) | ⏰ | ||||
| Monday | 9 | @TOR | Tylor Megill (R) | Ryan Burr (R) | W, 3-2 | 7.0 | 1.5 | 1.0 | +1.0 |
| Tuesday | 10 | @TOR | David Peterson (L) | Chris Bassitt (R) | L, 6-2 | 8.0 | 2.5 | 2.0 | 0.0 |
| Wednesday | 11 | @TOR | Sean Manaea (L) | Bowden Francis (R) | W, 6-2 | 8.0 | 2.0 | 1.5 | +1.0 |
| Thursday | 12 | 8.0 | 2.0 | 1.5 | +1.0 | ||||
| Friday | 13 | @PHI | José Quintana (L) | Aaron Nola (R) | W, 11-3 | 7.0 | 1.5 | 1.0 | +1.0 |
| Saturday | 14 | @PHI | Luís Severino (R) | Kolby Allard (L) | L, 2-1 | 8.0 | 2.5 | 1.0 | 0.0 |
| Sunday | 15 | @PHI | David Peterson (L) | Christopher Sánchez (L) | L, 6-4 | 9.0 | 3.5 | 2.0 | 0.0 |
| Monday | 16 | vs. WAS | Sean Manaea (L) | Jake Irvin (R) | W, 2-1 | 8.0 | 3.5 | 1.0 | +1.0 |
| Tuesday | 17 | vs. WAS | Tylor Megill (R) | Mitchell Parker (L) | W, 10-1 | 8.0 | 2.0 | 0.0 | +2.0 |
| Wednesday | 18 | vs. WAS | José Quintana (L) | DJ Herz (L) | W, 10-0 | 7.0 | 2.5 | 0.0 | +2.0 |
| Thursday | 19 | vs. PHI | Luís Severino (R) | Taijuan Walker (R) | W, 10-6 | 6.0 | 2.0 | 0.0 | +2.0 |
| Friday | 20 | vs. PHI | David Peterson (L) | Christopher Sánchez (L) | L, 12-2 | 7.0 | 3.0 | 1.0 | +2.0 |
| Saturday | 21 | vs. PHI | Sean Manaea (L) | Ranger Suarez (L) | W, 6-3 | 6.0 | 3.0 | 1.0 | +2.0 |
| Sunday | 22 | vs. PHI | Tylor Megill (R) | Zach Wheeler (R) | W,2-1 | 5.0 | 3.0 | 0.0 | +2.0 |
| Monday | 23 | 5.5 | 3.0 | +0.5 | +2.0 | ||||
| Tuesday | 24 | @ATL | Luís Severino (R) | Spencer Schwellenbach (R) | L, 5-1 | 5.5 | 4.0 | +0.5 | +1.0 |
| Wednesday | 25 | PPD | 6.0 | 3.5 | 0.0 | +1.0 | |||
| Thursday | 26 | PPD | 6.0 | 3.0 | 0.0 | +1.0 | |||
| Friday | 27 | @MIL | Sean Manaea (L) | Frankie Montas (R) | L, 8-4 | 6.0 | 4.0 | 0.0 | 0.0 |
| Saturday | 28 | @MIL | José Quintana (L) | Jared Koenig (L) | L, 6-0 | 6.0 | 5.0 | 1.0 | 0.0 |
| Sunday | 29 | @MIL | David Peterson (L) | Colin Rea (R) | W, 5-0 | 6.0 | 4.0 | 0.0 | 0.0 |
| Monday | 30 (1) | @ATL | TylOr MeGill (R) | Spencer Schwellenbach (R) | W, 8-7 | 5.5 | 3.5 | +1.0 | +0.5 |
| Monday | 30 (2) | @ATL | Joey Lucchesi (L) | Grant Holmes (R) | L, 3-0 | 6.0 | 4.0 | 0.0 | 0.0 |