He studied with Alfredo Lattaro, and, after winning an international voice contest, he made his debut in Spoleto, as Ruggero in La rondine, in 1962.
He quickly established himself throughout Italy, appearing first in lyric roles such as, Nemorino, Duca di Mantova, Alfredo, Rodolfo, des Grieux, Hoffmann, etc.
He began an international career in the early 1970s, with debut at the Vienna State Opera, the Salzburg Festival, the Paris Opéra, the Metropolitan Opera, etc., and began expanding his repertory to include more dramatic roles, notably Arnold, Don José, Manrico, Radames, Otello, Cavaradossi, Calaf, etc.
In his later career he became known for excessively long-held high notes (such as in "Di quella pira" and "Nessun dorma") and temperamental or bizarre behaviour, on and off stage.
He caused a major scandal in 1978 when, after throwing his prop sword at the conductor Herbert von Karajan, he furiously left the stage just before the famous cabaletta "Di quella pira" during a public dress rehearsal of Il trovatore at the Vienna State Opera.