From 1939 to 1946 he served as Harvard's baseball head coach, though no games were played in 1944–45 due to World War II; the team won its conference title in his first season in 1939, but his overall record at the school was 54–69.
Ohio State rehired Stahl the following year as their baseball head coach.
In 1950 he switched to the basketball program, becoming the head coach for the Ohio State men's team from 1950 to 1958.
While serving as the Ohio State basketball coach, Stahl was also an associate athletic director.
Stahl returned to coaching in 1966 to lead the Ohio State golf team.