Last night at la Scala, the opening night of Rigoletto, conducted by James Conlon with Leo Nucci as the giullare, whipped the audience into a frenzy of a final nine-minute ovation for the singer -- it was Nucci's 440th career performance of the part -- and the American conductor. If opera, like baseball, had a Hall of Fame, Nucci -- who's so humble he insists not to be addressed as maestro, even if he deserves the honor more than many, many conductors -- would be a first-ballot inductee .