IT was the briefest of phone calls but it could change a career forever.
When Irish soprano Celine Byrne was contacted on Tuesday night, she raced to Covent Garden in London.
She knew it was the moment which would propel her to the highest level of opera singing.
Just minutes beforehand -- and half-way through a 7pm production of the Czech opera 'Rusalka' -- lead vocalist Camilla Nylund declared herself unfit to go on. She had suffered an allergic reaction and couldn't sing.
London-based Ms Byrne, a mother of three from Naas, Co Kildare was the understudy and the stage beckoned.
Within minutes of arriving at the famous Royal Opera House she was centre stage.
"I was at home when I got the call saying that Camilla wasn't feeling well and how soon could I get there," she told the Irish Independent.
"I said I was on my way and I jumped in a taxi. I didn't even notice the traffic. I was just flicking through the score trying to be sure that I knew what I was doing because I had mapped out all the stage directions."
The former student at the Conservatory of Music in Dublin -- who went on to win the coveted Maria Callas Grand Prix in Athens in 2007 -- was conscious that many of the world's greatest singers had started out with exactly this kind of opportunity.
The rising star is hoping that more, if less frantic, opportunities might come her way.
"There are two more shows and you never know. Life in opera can change very quickly," she said.