At Cathedral High School in Springfield, he won all-state honors in football, baseball, and hockey, and was senior class president.

When Bertelli entered Notre Dame in 1940, he was 6 feet 1 inch and 173 pounds, a skinny but highly regarded tailback in the single-wing formation used by most college teams.

In the Heisman voting for America's outstanding college football player, Bertelli finished second in 1941 and sixth in 1942 before capturing the trophy in 1943.

After arriving from Guam in February 1945, he served in the Battle of Iwo Jima as a liaison officer with the 21st Marine Regiment,[2] where he was nearly killed when a Japanese mortar shell landed 15 feet away from his position; four others were also caught in the explosion, with a doctor suffering serious wounds but surviving.

[4] On January 1, 1946, he captained a Marine football team, the Nagasaki Bears, in the Atom Bowl against National Football League star Bill Osmanski and his Isahaya Tigers, where he threw two touchdown passes in the first half; although the two had promised to ensure the game end in a tie to promote unit morale, Osmanski scored the game-winning extra point in the 14–13 Tiger win.

Bertelli's son Mike quipped in 2005, "My dad didn't lose any sleep over it, but of all the games he played in, he remembered that incident.

[6] After returning to the United States in 1946, Bertelli signed with the Los Angeles Dons of the AAFC; he also recruited Atom Bowl players Bill Joslin and Gorham Graham, who were still stationed in Japan, to play with him.

[1] He was the color analyst for the Princeton University football games broadcast on radio station WVNJ, 620 AM and 100.3 FM in the 1950s and 60s.