Mautner played on Dr. Eddie Anderson's two undefeated football teams in the 1930s, and captained the 1937 squad that finished 8-0-2 and ranked 14th in the final Associated Press Poll. A durable two way center against the greatest teams that the Crusaders have played, he excelled on offense and as a roving linebacker on defense. He helped Holy Cross defeat national recognized powers like Georgia, Carnegie Tech, Colgate and Boston College. The three teams that he played on lost only twice, finishing 24-2-4. His coach Dr. Eddie Anderson considered him as one of the best in the nation, and this recognition gained him All-American Honorable Mention. Mautner also threw the discus under legendary track coach Bart Sullivan and competed in men's basketball.