Naturally opera fans — in New York and beyond — are a-twitter about how he'll do and what might happen. One poster to the famous opera blog Parterre Box made the most likely prediction: "I think he'll manage just fine. And I'm sure he is prepared for any kind of reaction and will keep his cool." Wrote another: "It would be nice to think that the Met audience can be more gracious and generous than that of La Scala."

How did this come about? Met general manager made a special request to Alagna yesterday when the scheduled Radames, Marco Berti, called in sick. The only problem was that Alagna was supposed to be singing Pinkerton in Puccini's Madama Butterfly last night, and doing the two roles on consecutive evenings would be a strain on any tenor. As it happens, the tenor who did Pinkerton in the same production last year, Marcello Giordani, is already on hand, playing Edgardo in the Met's Lucia di Lammermoor. So — in his second late-hour substitution within two weeks — Giordani stepped in for Alagna last night so that Alagna could step in for Berti tonight.

According to the Met's website, there are still some tickets (at the far ends of the price spectrum) available for tonight's performance of Aida, which stars Angela M. Brown in the title role, with Dolora Zajick as Amneris and Andrzej Dobber as Amonasro. And for those who can't be there in person, the Metropolitan Opera channel on Sirius Satellite Radio is broadcasting the opera live, beginning at 8 p.m. US Eastern time.