Renée Zellweger explains how she embodied Judy Garland — and how much she feared singing as her in 'Judy'

Renée Zellweger is drawing raves for her portrayal of stage and screen legend Judy Garland in the new biopic Judy, and rightly so.

The Jerry Maguire and Chicago actress, who took a six-year hiatus from movies earlier this decade, completely disappears underneath the skin of the late Wizard of Oz star in portraying Garland at perhaps her most vulnerable: while she struggled with addiction, depression, financial and parenting issues as she took a residency at London in the year before her death at the age of 47 in 1969.

For Zellweger, 50, it became an almost methodical approach to capturing Garland's iconic essence.

"It was just a process of experimentation," Zellweger told Yahoo Entertainment recently at a press junket during the Toronto International Film Festival (watch above). "We just started trying things from the beginning. … We just kept going through this methodology regarding every aspect of the performance."

"So it never really felt like this scary thing," she added before correcting herself. "Well, of course there was a lot of denial. But I didn't really look at it. I just stayed in the process and the work."

The scariest aspect for Zellweger, who won an Oscar for Cold Mountain (2003) and seems destined to earn a fourth nomination (if not triumph again) for Judy, was performing Garland's music.

"If I could've gotten out of it, I would've," she laughed. "And I'm pretty sure I tried pretty hard.

"I approached it, again, as there were recognizable aspects to her performance. The way that she sang, there was a method. And so I thought, 'OK, let me approach this cerebrally. She holds the microphone this way, and these are some of the things that are in her language, her performance. And this is how she enunciates, and this is what she does with the vowels. I'll just do it that way, I'll think about it that way, and let the other training take it where it will, and hopefully it will be what it needs to be.'"

Judy opens Friday. Watch the trailer:

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