During his nearly 40 years at UNM, Johnson coached every men's sport the school offered, while teaching physical education. A decorated veteran who served in World Wars I and II, he was the UNM athletic director from 1920–49. He established regularly scheduled games against regional colleges, and in 1931 UNM joined the Border Conference as a founding member. Johnson coached the UNM basketball team for all but two seasons from 1920–40. From 1924–34, his teams posted a 104–38 (.732) record. The Lobos won 165 games with Johnson as head basketball coach, a school record for over 30 years and currently third on its all-time list.