 Urlus tried to sing in spite of a heavy head cold and lost his voice completely during the second act of "Tristan und Isolde", having to resort to pantomime in act three.Still, when he sang the lead role in "Siegfried" only a week later he not only restored his reputation completely but cemented his position as the Met's number one (and, later, its sole) heldentenor.Urlus' Metropolitan Opera career was cut short in 1917 when the United States entered World War I and Wagnerian operas were banned for the duration.