The Spanish tenor fell ill with a cold on Friday (03Apr15), prompting the Met's general manager, Peter Gelb, to contact Salsi ahead of the weekend concert of Verdi's Ernani as a possible stand in.

Gelb reached out to the Italian singer again on Saturday morning to notify Salsi his services would no longer be needed, but plans changed again shortly before showtime, when Domingo's daughter, Alvaro, called the star in a panic and asked him to rush to the Met to take her father's place as Don Carlo, as he did not feel well enough to take the stage.

Salsi, who was already scheduled to perform in Donizetti's Lucia di Lammermoor at the Met later on that night, agreed and made it to the stage just in time for the event, which was broadcast on radio networks around the world.

The 40 year old had no time to review Verdi's score, but he admits the lack of time actually helped his performance.

He tells the Associated Press, "(It's) better like this because I didn't have the time to think and be nervous. Just go and sing."

Salsi had previously performed the role of Don Carlo in Rome, Italy in December, 2013, under the direction of revered conductor Riccardo Muti, and he reveals, "When you do something with maestro Muti, after you will remember very well the score (sic)."

Domingo showed his support for Salsi during Saturday's show by cheering him on from the side of the stage.

Salsi went on to take centre stage at the Met hours later for his scheduled performance in Lucia di Lammermoor.