There were some variations from the classic story's usual script, of course. The star whom Alvarez replaced didn't suddenly fall ill: she was fired four days before opening. Because the diva was dismissed for missing too many rehearsals, Alvarez, who had been filling in for her absent colleague, was already well-rehearsed. And the director, Renata Scotto, was in her own day a great Mimì and gave her young charge the benefit of long experience.

Nevertheless, when Alvarez took the stage on October 1, she was giving her first performance in any major opera house. (The largest company with which she had sung before this week was Oper Leipzig in Germany.)

Her reviews were the stuff young singers dream of.

"Far from displaying any obvious nerves, Alvarez looked and sounded like a poised veteran," wrote John von Rhein in The Chicago Tribune. "The voice bloomed under pressure the way you want a Puccini voice to bloom, yet kept its warm tonal finish when she floated the high pianissimos opera lovers wait for in rapt anticipation."

For the Chicago Sun-Times, Wynne Delacoma wrote that "[Alvarez's] Mimì was clearly passionate, and the dark cast to her strong, well-projected soprano added depth and emotional richness to her initial duet with Roberto Aronica's Rodolfo. By the festive Café Momus scene in Act II, her singing had become juicy and lyrical, and her wrenching Act III encounter with Rodolfo, frantic at the thought of Mimì's impending death, was luminous."

Elaine Alvarez sings Mimì in Lyric Opera of Chicago's La Bohème — opposite Roberto Aronica (Rodolfo), Nicole Cabell (Musetta) and Quinn Kelsey (Marcello) — again tonight and for four further performances through October 16. Serena Farnocchia and Gwyn Hughes Jones take over the roles of Mimì and Rodolfo for an additional five performances November 9-23. Information and tickets are available at www.lyricopera.org.