In his first term as coach, 1909 to 1910, he posted a record of 10–1–3, but this was exclusively against southern California competition, with no major colleges on the schedule. Like many schools, USC switched from football to rugby, from 1911 to 1913. Cromwell returned as football coach in 1916, by which time USC's teams had begun to be known as the Trojans.
During his initial coaching term (1909-1910), he had a record of 10 wins, 1 loss, and 3 ties against Southern California opponents. This was the same period when USC switched from football to rugby between 1911 and 1913. Cromwell returned as head coach in 1916, coinciding with the adoption of the "Trojans" nickname for USC's teams.