Armstrong played nine seasons in the
American Hockey League (AHL) and the
International Hockey League (IHL) and served as head coach for the AHL's
Providence Bruins and
ECHL's
Trenton Titans, both for two seasons. He was previously the
St. Louis Blues' assistant general manager and director of amateur scouting. In September 2020, Armstrong was hired to be the general manager for the
Arizona Coyotes, going on to sign a multi-year extension in September 2023. ==Career statistics==