After the opening night of Covent Garden’s new Don Carlo just over a week ago, the world of opera — managements, agents, record companies, audiences and, yes, even critics — will have to get used to a couple of inconvenient truths: Rolando Villazon’s comeback, after five months of rest and regrouping last year, that greeted his curtain call. I don’t want to give too much credence to an isolated protester, but this is something I never expected to hear for such a popular star at the ROH.

It should be clear by now that Villazon is not, never has been and never will be the “new Domingo”. Don Carlo was one of Domingo’s greatest roles — one that he sang on almost every major stage except, alas, Covent Garden — but at Villazon’s age, 36, the Spanish tenor was already singing Verdi’s Otello, the weightiest assignment in the Italian repertoire, and had most of the big Puccini and verismo roles under his belt.

With hindsight, it is easy to see how we have all been seduced by the sound of Villazon's voice. When I first heard it on disc, in a small role on Daniel Barenboim’s recording of The Flying Dutchman, I thought the timbre reminiscent of Domingo in his prime, but I revised my opinion when I first heard him in the theatre, as Rodolfo in La bohème at Glyndebourne in 2003. His is a much smaller voice than Domingo’s, but its dark, almost baritonal sound is deceptive. Dark-sounding tenors are usually heroic tenors, but Villazon is the exception, a dark, super-lyric tenor — a unique voice in my experience. Some serious repertoire rethinking is now urgent. Otherwise audiences will be bravoing Villazon into oblivion or the amplified arena-concert circuit.

Both Antonio Pappano, the Royal Opera’s music director, and Nicholas Hytner, the stage director of Don Carlo, do their utmost to minimise Villazon’s shortcomings in Verdi’s demanding title role by keeping the orchestra down for his big dramatic outbursts and keeping him close to the front of the stage. Whenever Villazon sang upstage, his voice almost disappeared, but it was his strangulated assaults on the high notes, and the look of sheer panic he gave Pappano in the garden scene, when his pitching went horribly awry, that gave the game away. Despite some lovely mezza voce (half-voice) phrases — Villazon is one of the most musical young singers around right now — the vocal fire power required for Don Carlo is really beyond him.

With one exception, Covent Garden has surrounded a feather-weight protagonist with equally lyrical singers, a risk that pays off only in Simon Keenlyside’s handsome, athletic, sturdily sung Marquis de Posa. It’s hard not to draw the conclusion that the young principals have been cast for their looks: Marina Poplavskaya, only a year after leaving the RO’s young artists programme, is a blonde vision, especially as the youthful Elisabeth de Valois, scampering around the forest of Fontainebleau and shooting with the hunt. Physically, the Russian soprano and Villazon are ideally matched, but the role takes an even heavier toll on her big-sounding but bleached-toned soprano. By the time she gets to her big moment in Act V, at the tomb of the emperor Charles V, she is all but sung out, snatching for notes at either end of the vocal compass and woefully out of tune. Poplavskaya has been fast-tracked to the front line of opera stars, but she hasn’t fulfilled the huge promise of her Rachel in Halévy’s La Juive in concert two seasons ago.

Sonia Ganassi’s Princess of Eboli is another case of wishful thinking on her and the RO management’s part: a superb heroine in Rossini’s La Cenerentola, she manages the filigree turns of Eboli’s Saracen Song with detailed aplomb, but she lacks the vocal guns for the garden scene trio and her barnstorming envoi, O don fatale (O fatal gift).

For much of the evening, Pappano seemed to be nursing these relatively fragile Verdi-lite voices, robbing the score of its essential drama. Things looked up at the beginning of Act IV, when Ferruccio Furlanetto’s majestic Philip II held the house spellbound for his gloomy interior monologue of self-recrimination. Finally, the music had found a near-ideal interpreter — a voice of stature and a charismatic actor deeply inside the psychology of his role. His confrontation with Eric Halfvarson’s booming Grand Inquisitor, a poisonous toad in cardinal’s scarlet, bristled with theatricality as the all-powerful king crumbles before the might of the Church in the form of the blind nonagenarian cleric.

This was one of the few moments when Hytner’s production rose superbly to the challenge of Verdi’s sprawling masterpiece. Elsewhere, the National Theatre director’s response to Verdi’s epic theatre looked anodyne and lacklustre, although, typically, he gets memorable physical performances from Villazon, Poplavskaya

and Keenlyside. Bob Crowley’s designs are part of the problem: his imprisoning walls serve well an opera that juxtaposes stifling claustrophobia and religious repression, but the auto-da-fé scene, with screaming heretics, a baying

populace, is pure kitsch, and the orange wall of the convent garden scene is both hideous and baffling. When faced with an international opera budget — and this is a co-production with Oslo and New York’s Met — theatre directors and designers think they have to do spectacle, but the Hytner-

Crowley Don Carlo is a half-and-half mishmash of traditional representationalism and postmodern symbolism. Expectation ran high — too high, perhaps — for this Don Carlo, so this may explain my disappointment.

The first night was a predictably glitzy affair with Hytner supporters Alex Jennings, Frances de la Tour and her History Boys co-star Dominic Cooper prominent among occupants of the stalls. Also in attendance was an evidently pregnant Anna Netrebko, who had popped over from Paris, where she had been making her Opéra-Bastille debut as Giulietta in Bellini’s Romeo and Juliet opera, The Capulets and the Montagues, to cheer on her friend and stage partner, Rolando. At the weekend, I caught her last performance before her baby is due, and she was in more radiant voice than I have ever heard her, duetting gloriously with Joyce DiDonato’s velvet-toned Romeo. Netrebko is to sing Giulietta at Covent Garden next season — alas, without DiDonato — so Royal Opera audiences are in for a treat. Giulietta is as near-perfect a fit for Netrebko as anything I have heard her sing, and she looks as good as she sounds. Only when she was laid out in her tomb was one aware of her happy forthcoming event in September.

Don Carlo is relayed live on outdoor screens around the country on July 3, details from www.roh.org.uk/bpbigscreenslive ; Radio 3 broadcasts it on June 28

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