Background
Mitterwallner was born in Trumansburg, New New York
Mitterwallner was born in Trumansburg, New New York
He played college football at the guard position at both the University of Denver and the University of Illinois at Urbana–Champaign. While playing for Illinois, he was a key blocker for Red Grange and was selected by Herbert Reed as a first-team player on the 1925 College Football All-America Team. He also received third-team All-American honors from the International News Service and the Chicago Daily News.