Kelly Clarkson, Simon Cowell exchange sweet messages as she covers for him on 'AGT'

Clarkson is filling in for Cowell as he recovers from a serious back injury.
Kelly Clarkson steps in as guest judge on "America's Got Talent" as Simon Cowell goes on leave from the reality competition show to recover from surgery.
Kelly Clarkson steps in as guest judge on "America's Got Talent" as Simon Cowell goes on leave from the reality competition show to recover from surgery.NBC
/ Source: TODAY

Kelly Clarkson filled in for Simon Cowell on “America’s Got Talent” last night as he recovers at home from a serious back injury, and she fit right in at the judges’ table.

The singer and “Voice” coach revealed how she prepared for her guest judging gig, and the pressure she felt to fill Simon’s shoes.

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“All right, y’all, so Kelly Clarkson here, taking over for Simon Cowell,” she said in a Twitter video before the show. “I’ve just been kind of working on my lines, some of Simon’s best lines, because I’ve got a reputation to uphold.”

She then tried out some classic Simon lines in a British accent, including, “I don’t like it … I love it,” and “What the bloody hell was that?”

In the end, though, she decided to bring her own spin to the judging table.

“I have the worst British accent in the entire universe so I’m just going to bring country to 'AGT' tonight!” she said.

Cowell had a sweet response to Clarkson’s video, writing to the singer on Twitter, “Thank you @kellyclarkson. Miss all of you. What a Great Show.”

It was really a full circle moment for Clarkson, who rose to fame after she auditioned for “American Idol” in front of Cowell back in 2002.

The "Voice" coach was a natural on "AGT"!NBC

The singer killed it as an “AGT” guest judge and after the show, she admitted she could get used to appearing on the reality competition series.

“Um Simon, don’t hurry back,” she said in another video on Twitter. “I’m getting real comfortable in your chair. I look pretty good in it! I’m just kidding, get well.”

Cowell broke his back on Saturday in a serious bike accident. He underwent a six-hour surgery, which involved multiple fusions and a metal rod being placed in his back, a rep told TODAY over the weekend.

He is now recovering from surgery, and Clarkson is filling in for him during this week’s live shows.

“My friend, Simon Cowell, is doing better now but was in an accident and won’t be able to make Tuesday and Wednesday’s live shows for ‘AGT,’ but no worries America, someone far wiser, cooler, and hotter is taking his seat!” Clarkson joked on Twitter. “The unbelievably amazing Kelly Clarkson. You’re welcome in advance!”

Cowell kept things positive when he updated his fans about his injury on Twitter.

“If you buy an electric trail bike, read the manual before you ride it for the first time,” he joked. “I have broken part of my back. Thank you to everyone for your kind messages.”