He is currently a player development coach with the Boston Celtics of the National Basketball Association (NBA).
McMains was born in New Hampshire in the United States before growing up in New Zealand on Waiheke Island.
[2] During this time, he studied at Santa Monica College (2008–10) and John Cabot University (2011) in Rome, Italy.
[10] In May 2021, McMains was appointed an assistant coach with the Louisville Cardinals men's college basketball team.
[11] For the 2022–23 season, McMains served as the associate head coach of the Maine Red Claws of the NBA G League.