Hegerle made his professional debut against Walter Quinn on June 8, 1954, recording a win by fifth-round knockout.
The loss didn't deter Hegerle, in fact his early career was sprinkled with occasional losses and draws, but he continued to fight frequently, and by April 1956 Hegerle had compiled a record of 19–3–2.
In May Hegerle faced his first notable opponent, Jimmy Martinez, whose record was 69–23–9.
Martinez beat him on points, but in a rematch only two weeks later, Hegerle returned the favor.
Hegerle retired from professional boxing with a record of 36–18–3 with 20 wins coming by knockout.