sixth men

Noun

sixth man (plural sixth men)

1. A player who is not a starter but comes off the bench much more often than other reserves.
2. By extension, a person or group who is not part of a team, but who supports or contributes to the success of the team.
   • Our sixth man, the Williams Arena crowd, was into the game, all 15,491 of them.1997, Clem Haskins, Marc Ryan, Clem Haskins: Breaking Barriers, page 143