On December 30, 1898 she was to sing Isolde to the Tristan of the legendary Jean de Reszke at the Metropolitan Opera House. Nordica was reclining on her couch during the long and quiet prelude, patiently waiting for the curtain to rise, when the stage manager noticed that her eyes were closed and her breathing somewhat shallow and regular. He realized she had fallen asleep while the conductor creeped along at a snail's pace with the music and panic struck him. Much to his consternation, when the curtain arose, Nordica still did not open her eyes! However, once the sailor's song was finished, she sprang into action with an electric intensity that was uncommon for her. The sudden rise in music had startled and awakened her and she immediately began to sing, Nordica was, as usual, in complete control of the situation.
One must realize that this lady had current in her repertoire: La Traviata, Faust, Les Huguenots, L'Africaine, Tristan und Isolde, Mignon [Philline], all 3 Ring Brunnhildes, Hamlet, Lohengrin, Il Trovatore, Aida, and La Gioconda. She sang them all actively in her repertoire and she sang them all well according to contemporary accounts.