“I’m gonna preface [this] with no one should ever sing this song, but I got tricked one time,” Clarkson said, leading into the second-to-last song of the night, a Kellyoke cover of Dolly Parton’s “I’ll Always Love.”

Speculation has been high for weeks that Clarkson would do the song after she posted a photo on Instagram of the Caesars Palace marquee — showing her shared billing with Parton, who will debut her residency at the theater Dec. 4 — and commented, “I ​​think this is a sign I should cover a Dolly song at one of my shows… but which song?”

Parton clapped back with, “Hey Kelly, I think you should sing “I Will Always Love You” because I think you do one of the best versions of that song that I have ever heard… Whitney and I would both be proud.”

Then came a long soliloquy about Parton and the song. “She’s a beautiful human and she’s so sweet. Early in my career, she was kind, and that matters, especially for younger artists who are fearful of looking stupid.”

“[An awards show asked me] to sing this tribute to her. I said, ‘Absolutely.’ Then they’re like, ‘She picked, I Will Always Love You.’ I was like, ‘Have a good night.’ No singer in the world, on their best day, wants to sing ‘I Will Always Love You.’ I was terrified. She’s standing on the side stage. I was like, ‘Oh my God, that’s like the principal watching you do math on a chalkboard.’”

Clarkson also gave props to Whitney Houston. “You can tell by some of my runs. I’ve been taking a little run here, a little run there from her, because I grew up on her. These are two of my favorite musical influences and it’s such a beautiful song. We tried to do a marriage of both artists. We all know The Bodyguard. I’m from Texas, so the very first version I heard was Dolly.”