At what moment does a “rising star” become simply a “star”? A crucial step toward that operatic pinnacle may have occurred Wednesday evening at the Metropolitan Opera when soprano Sonya Yoncheva triumphed in her first US Violetta. Since its premiere there in 2010, Willy Decker’s starkly devastating production of Verdi’s La Traviata has been waiting for the ideal protagonist to don Wolfgang Gussmann’s iconic red dress and with its sixth soprano she has arrived.

Yoncheva seems poised to join an impressive group of Bulgarian sopranos appearing at the world’s greatest opera houses over the past 40 years including Raina Kabaivanska, Anna Tomowa-Sintow, Ghena Dimitrova, Krassimira Stoyanova and Alexandrina Pendatchanska (now Alex Penda). Strikingly lovely with a pale, expressive face, Yoncheva displays a bright, secure soprano with an intriguingly smoky middle register and wields it with a wrenching morbidezza that makes her an ideal exemplar of some of opera’s most heart-breaking heroines.

From her first world-weary entrance during the prelude, this Violetta was striking for being both exceptionally self-possessed and shockingly young, reminding us that Marie Duplessis, on whom Alexandre Dumas based his heroine of La Dame aux Camélias, was just 23 years old when she died. Yoncheva’s courtesan was clearly aware of her attractiveness to men, teasing seductively members of the (apparently) all-male chorus and toying playfully with the love-struck Alfredo of Francesco Demuro.

The great scena that concludes Act I proved a searing glimpse into Violetta’s haunted soul rather than an occasion for vocal display. However, those who obsess about high notes (not written by Verdi) might snipe that Yoncheva eschewed the “expected” E-flat at the end of “Sempre libera.”

With the implacable Germont of Quinn Kelsey, the great Act II duet demonstrated the soprano’s gift for combining strength and vulnerability. Particularly impressive was her exquisite “Dite alla giovine” spun on a merest thread of tone that was still always splendidly audible. Her “Amami Alfredo” may have lacked the ideal amplitude and emotional punch, but “Alfredo, Alfredo” achingly reflected the wounding shock of Alfredo’s brutal denunciation which in Decker’s production has him mercilessly fling wads of cash at the supine Violetta, even stuffing bills between her legs.

Even in productions less bleak than Decker’s I frequently become impatient by the end wanting Violetta to just get on with it and die. Yet Yoncheva made the final act seem not a moment too long as she relished both verses of “Addio del passato.” Miraculously, her vivid determination nearly convinced us that she would recover and find happiness with Alfredo.

Though I’d previously seen it performed by Marina Poplavskaya, Natalie Dessay and Marina Rebeka, Decker’s stark staging of Violetta’s death proved particularly shattering in Yoncheva’s chilling interpretation. Not surprisingly when the curtain rose again to reveal the depleted soprano on that vast empty white stage, the ovation was ear-splitting.

Yet it wasn’t only Yoncheva’s night—Demuro, her ardent Alfredo, has had unexpectedly eventful season at the Met. Scheduled to debut in late December in Traviata, he was called on earlier to be one of the three (!) tenors to replace Ramon Vargas opposite Yoncheva during her Bohème run.

And on the opening night of Traviata last month, the curtain was held for nearly a half an hour while Demuro was rushed in to replace an ailing Stephen Costello who canceled at the last minute. I attended that performance and Demuro proved a real pro. channeling any nervous energy into an intensely appealing portrayal.

Accompanied with unfailing sensitivity by Marco Armiliato, Wednesday’s Alfredo was perhaps less exciting, less emotionally “naked” than at the premiere, but it was still very accomplished. If he lacked the ringing power for the big gambling scene ensemble, he brought a well-schooled, vibrant tenor–complete with a pingy high C for the end of his cabaletta.

Baritone Kelsey has also frequently been called a “rising star” but, like Yoncheva, there was nothing “rising” about his superb Germont. He effortlessly poured forth oceans of handsome mahogany tone, sculpting one of the more eloquent renditions of “Di Provenza” I have heard, rightly earning a hearty ovation for it.

He entered fully into the production’s ice-cold vision of a rigid and brutal Germont who refuses to embrace the shattered Violetta at the end of their duet and who slaps his bereft son when he refuses to accept Violetta’s farewell. When opera-lovers frequently mourn “Where are today’s Verdi baritones?” many have been pointing to Kelsey who has recently had great successes as Rigoletto, di Luna and Ezio in Attila but conspicuously not at the Met. One hopes these sterling Traviatas (replacing the absent Ludovic Tézier) will help to change all that.

Although I missed both her well-received Met debut last season as Gilda and her hastily-scheduled first-ever Mimi there in November, this Violetta was not my first encounter with Yoncheva in New York City. In 2007 her first big “break” was to be selected to be part of “Le Jardin de Voix,” a biennial program by the early-music group Les Arts Florissants to cultivate young singers. Her charismatic “star” quality was apparent from the first as can be seen in a documentary made about that year’s crop of singers.

Each “Jardin” tours widely and I attended its concert at Alice Tully Hall in March of that year, but I simply don’t recall Yoncheva making a particularly striking impression.

However her return to New York three years later with Les Arts Florissants was quite a different matter. A bare-bones production of Purcell’s Dido and Aeneas (on a double-bill with Charpentier’s Actéon) was staged just for that visit to the Brooklyn Academy of Music starring Yoncheva as Dido and I remember not liking her at all. Her interpretation struck me as too melodramatic, too Romantic, too voluptuously sung to fit the very otherwise very restrained and HIP production.

Nonetheless she continued until recently to sing a lot of 17th and 18th century music including a number of shows tied to the Pergolesi tercentenary.

She has also often sung with Emmanuelle Häim and Le Concert d’Astrée with whom she appeared as both Monteverdi’s and Handel’s Poppea.

But I was not surprised when I learned she had won Placido Domingo’s Operalia, the decidedly non-Early Music vocal competition, in 2010. This win has led her to reinvent herself as a soprano with a more mainstream repertoire, making her biggest splash by replacing Dessay as all of the heroines in Offenbach’s Les Contes d’Hoffmann in Paris in late 2012.

Releasing a solo CD seems an inevitable step to opera fame and fortune so Yoncheva’s recent exclusive contract with Sony is bearing fruit at precisely the right moment: “Paris, Mon Amour” was released in the US on Tuesday.

It’s a canny program neatly conceived to show off the soprano’s strengths in a mixture of well-known Italian works and lesser-known French ones. A quick listen revealed several highlights: the opening “Il est doux, il est bon” from Massenet’s Hérodiade is lovely as is Anna’s aria from Puccini’s Le Villi.

“O ma lyre immortelle” from Gounod’s Sapho is usually claimed by mezzos (although Régine Crespin also recorded a ravishing version) but Yoncheva does it well if occasionally lacking the expected rich lower register.

Mimi’s farewell may lack the heartbreak heard in her recent Met appearances,but high-note aficionados will find Violetta’s high E-flat here. The recording sometimes emphasizes a thinness or edginess to her high notes that was less apparent at the Met and her charming version of a ditty from Lecocq’s Les Cent Vierges reveals a less-than-satisfactory trill, but all in all this CD is a happy sampler of Yoncheva’s art.

Peter Gelb has clearly decided that Yoncheva merits a prominent place at the Met. Due to the craziness of artistic planning done years in advance, her Met debut was actually supposed to have been tonight (January 15th) as Musetta opposite tenor Jean-François Borras who was her very first Alfredo just over two years ago.

But cancelations by other prima donnas have prompted the MET to step up its game and schedule instead three prominent engagements. She’s also now scheduled to open the MET’s 2014-15 season with her first-ever Desdemona in a new production of Verdi’s Otello.

But before the fall, three more Traviatas (with Aleksei Markov as Germont) at the Met remain and they immediately become “must-attend” events, as do her upcoming Violettas at Covent Garden this spring. However, for those who may not be able to experience this memorable portrayal in the flesh, next Wednesday’s performance of La Traviata will be streamed live on the MET’s website.

Photo: Ken Howard / Metropolitan Opera