Tackle at the University of Notre Dame, he was 1968 consensus First-team All-American and a member of 1966 Notre Dame national championship team. He was a two-year starter at right offensive tackle and co-captain of Irish team in 1968. In addition he was National Football Foundation Scholar-Athlete honoree in 1968, being voted Academic All-American in 1968 and winner of NCAA post-graduate scholarship.
Kunz was selected in the 1st Round of the 1969 NFL Draft by the Falcons with the 2nd overall selection.
Kunz established himself as one of the premier offensive linemen of his generation, being named to the Pro Bowl team 8 times (1969, 1971-'77) in a 9-year span. In addition, Kunz was named All-Pro in 1972, 1973 and 1975, 2nd Team All-Pro in 1976 & 1977. Kunz was also All-Conference in 1973, 1975, 1976, and 1977 and 2nd team All-Conference in 1972 and 1974.