On September 22, 1956, La Nelli created the role of Bethsheba in the American premiere of Darius Milhaud's David, co-starring Harve Presnell, Mack Harrell, and Giorgio Tozzi, conducted by Izler Solomon, and staged by Harry Horner.
He began his career with the New Orleans Opera Association in secondary parts, including appearances in Salome (1949), Le nozze di Figaro (1956), Il trovatore (opposite Herva Nelli, 1958) and The Beggar's Opera (directed by Lillian Gish, 1958).
Toscanini: The Maestro is the last television program narrated by Alexander Scourby, is hosted by James Levine, and features interviews with former NBC Symphony Orchestra members, as well as reminiscences by opera stars Robert Merrill, Jarmila Novotná, Herva Nelli, Licia Albanese, as well as Bidu Sayão, all of whom worked with Toscanini, and rare color home-movies of the maestro with such musicians as Vladimir Horowitz and Andrés Segovia.