| 1 | 3062 | 9/11/21 2:30pm | CCHS Turf 2A | C-C Union | 1 - 1 | Belmont Mastiffs | |
| 2 | 3065 | 9/18/21 2:30pm | PQ (1A) | Belmont Mastiffs | 2 - 1 | Winchester Winchester Warriors | |
| 3 | 3069 | 9/25/21 12:00pm | Downes Field (oval) | Brookline Santos | 3 - 0 | Belmont Mastiffs | |
| 4 | 3070 | 10/2/21 11:45am | Teddy Ebersols Red Sox Field 9v9 (1) | Hill House United Blue | 2 - 3 | Belmont Mastiffs | |
| 5 | 3074 | 10/8/21 5:00pm | PQ (1A) | Belmont Mastiffs | 2 - 2 | Parkway United Blue | |
| 6 | 3077 | 10/16/21 2:30pm | PQ (1A) | Belmont Mastiffs | 1 - 4 | C-C Union | |
| 7 | 3081 | 10/23/21 1:30pm | Ryan Connolly Field 9v9-Back | Winchester Winchester Warriors | 2 - 1 | Belmont Mastiffs | |
| 8 | 3084 | Unscheduled | PQ (1A) | Belmont Mastiffs | F - 1 | Brookline Santos | |
| 9 | 3086 | 11/6/21 2:30pm | PQ (1A) | Belmont Mastiffs | 2 - 1 | Hill House United Blue | |
| 10 | 3089 | 11/13/21 2:30pm | Millennium Park C | Parkway United Blue | 2 - 2 | Belmont Mastiffs | |
