Portraying Judy Garland in “Judy” presented some real challenges for Renee Zellweger. The actress dished on the role while visiting “The Ellen DeGeneres Show” on Wednesday.

“That stage-fright scene, that was real,” Zellweger said. “You know, it’s a real audience where we filmed it.”

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“Rupert [Goold], the director, was determined that this was going to be an authentic experience between a performer and an audience,” she continued. “It’s the end of her life, maybe the last year of her life. She did a series of concerts in London.

“A lot of people think it was the tragic part of her life but I think understanding the circumstances, in context, you can see how extraordinary she really was.”

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Zellweger continued to build Garland up.

“Not just her God-given talent but with the things she was able to overcome in order to continue to perform in that level,” she told DeGeneres. “She is remarkable, one in a million.”

“Judy” premieres Sept. 27 in theatres.