Born in Braco in Perthshire, Scotland, McGregor first became interested in football after watching a match between locals and visiting artisans at Ardoch. He served an apprenticeship as a draper in Perth, and in 1870, following the example of his brother Peter, moved to Birmingham, and opened his own drapery business in Aston, an area just outside the city. Upon his arrival in the English Midlands he became involved with a local football club, Calthorpe, which had been formed by a fellow Scot, Campbell Orr. McGregor was enthusiastic enough about the game to arrange for his shop to close early on Saturdays to allow him to watch matches, and he later sold football kits at the shop, which became a popular meeting place for football enthusiasts.