McNair was a solid lefthanded hitter with speed to burn. Like many other Negro League stars, he played for the 25th Infantry Wreckers, based at Fort Huachuca, AZ. In 1915 he was a member of the champion Chicago American Giants. From 1920 through 1927, he batted .320 with the Kansas City Monarchs, playing on the 1923-25 champions, and leading the team in home runs in 1927. Upon retiring as a player, he became a Negro National League umpire, earning about $140 a month.