(UPDATED) In what she considers the "hardest performance of her career," KZ Tandingan took the stage in China's "Singer 2018" with a Mandarin medley, in a bid to stay on in the competition watched by hundreds of millions.

She sang「你不知道的痛」 or "The Pain which You Don't Know" in English.

"I want to show my respect to the Chinese audience, Chinese culture, Chinese music," Tandingan said in an interview shown before her performance, explaining why she opted to sing in Mandarin.

She added: "I actually heard this song by accident. I instantly fell in love with the melody of the song. When I found out what the song really meant, I fell in love with the song."

Tandingan, who hails from Digos, Davao del Sur, was also seen practicing Mandarin lines in behind-the-scenes footage aired prior to her turn on stage.

"I ask them, 'How do you position your tongue and your teeth so you can pronounced that word?' I hope if I don't get it perfectly, I hope I can go close to the almost perfect pronunciation," she said.

In a press conference early this week, the "X Factor" winner referred to her Mandrin as "one of the most challenging, if not the most challenging" performance she has done in her six-year career. "Hindi ko akalain na kakayanin ko gawin at aralin in a span of two weeks," she said.

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This is in contrast to her previous "Singer 2018" performance of Adele's "Rolling in the Deep," which she had already covered numerous times in the Philippines.

Tandingan, 25, is the lone Filipino in the weekly TV show, where she is up against the likes of UK pop star Jessie J, and other superstars from China, Taiwan, and Hong Kong.

The Kapamilya singer debuted as a challenger in the February 9 episode of "Singer 2018," where she placed first in the ranking of eight determined by audience votes. Jessie J, her idol, placed second.

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That first-place finish was important for Tandingan. As a challenger, she needs to average in the top four after her first two episodes, in order to become a permanent contender.

As of writing, the ranking had yet to be announced for "Singer 2018's" sixth episode overall and Tandingan's second.

Tandingan, whose showbiz career started via "The X Factor Philippines," is aiming to stay until the April 13 live finale of "Singer 2018." While she is not aware of any monetary prize for winning overall, Tandingan has said she considers the exposure to the hundred millions-strong Chinese audience an incomparable award in itself.

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