The left half in the great Bethlehem Steel half back line of McDonald, Carnihan and McGregor, Bob came to the United States from Scotland one year after leading Morton to a 1-0 triumph over Rangers in the Scottish Cup Final. He remained with Bethlehem Steel from then until the summer of 1930 when the team folded, and he moved with most of the former Bethlehem players to Newark, New Jersey. McGregor was one of the finest wing halves in the history of the ASL.
Source: Colin Jose, Historian, National Soccer Hall of Fame