Public criticism of performers by management is rare in classical music, but Lyric Opera general director William Mason took the unusual step of detailing the reasons for the dismissal.

"Miss Gheorghiu has missed six of 10 rehearsals, including the piano dress rehearsal and both staging rehearsals with the orchestra," Mason said. "She missed one of the most critical stage-orchestra rehearsals when she left the city for New York without permission, a direct violation of her contract."

Gheorghiu, a 42-year-old Romanian widely admired for her vocal allure and dramatic abilities, is married to tenor Roberto Alagna, who is currently performing at New York's Metropolitan Opera.

Mason said she had demanded new costumes for her performances in the Puccini opera, then refused to attend fittings.

"It is with tremendous regret and sadness that we are compelled to take this action," Mason said, "but Miss Gheorghiu's actions have shown total disregard for Lyric Opera's dedicated personnel and for her fellow artists."

Gheorghiu said she left Chicago to spend time with her husband, who is singing at the Met in Gounod's "Romeo et Juliette" with soprano Anna Netrebko and rehearsing for Puccini's "Madama Butterfly."

"I asked Lyric Opera to let me go to New York for two days to be with him, and they said, `No.' But I needed to be by Roberto's side at this very important moment," Gheorghiu said in a statement. "I have sung `Boheme' hundreds of times, and thought missing a few rehearsals wouldn't be a tragedy. It was impossible to do the costume fitting at the same time I was in New York.

"Coming back from New York, I caught a cold -- a most unfortunate coincidence. I saw the company doctor when I returned, and he prescribed antibiotics. I just wanted to get well. My colleagues knew about this and were supportive. Of course, I'm very sad that this has happened, as I was very eager to sing in Chicago."

Gheorghiu and Alagna were publicly rebuked in 1998 by the Met when then-general manager Joseph Volpe withdrew their contracts for a new production of Verdi's "La Traviata," saying they wanted design and direction approval. And last December, Alagna walked off stage after he was booed following his opening aria in Verdi's "Aida" at Milan's La Scala, creating an international stir.

While most operatic disputes are handled privately, several famous singers have been involved in previous public flaps. In November 1958, Met general manager Rudolph Bing fired Maria Callas when she asked to be relieved from two performances in "La Traviata." And in 1989 the Lyric "banned" Luciano Pavarotti from future engagements for excessive cancellations.

Gheorghiu's understudy, Elaine Alvarez, will make her Lyric Opera debut and replace Gheorghiu in six performances starting Monday. Mason said in a telephone interview that Gheorghiu has no other future contracts at the Lyric Opera and it was too early to say whether she would be invited back.

Also Friday, the Lyric announced an agreement with the American Guild of Musical Artists that averted a threatened strike of Saturday's season-opening performance of "La Traviata." The agreement is subject to ratification by the union.