Slated to be one of the night's headliners on the stage that first made her a star, host Ryan Seacrest shared that it was a potential Covid scare that kept her away.
VIDEO: Carrie Underwood announces epic 43-date tour
After introducing the incredible line-up of performers for the night, he explained: "There was a Covid exposure within Carrie Underwood's group, so following protocol, she's unable to perform tonight. Sad."
Immediately, fans in the audience started groaning and booing out of disappointment, and even judge Lionel Richie expressed his sadness.
"But you can check her out on her tour, Denim and Rhinestones, coming this fall. Go see her," Ryan enthusiastically added at the end.
Carrie was unable to perform on American Idol due to possible Covid exposure
Others took to social media to express their thoughts, with one saying: "Hopefully she is feeling well and didn't get Covid!" and another adding: "Now I'm bummed right now that I found out that @carrieunderwood won't be performing at the American Idol finale and that her team has covid exposure, I wish them a speedy recovery, this is news I wasn't expecting."
The Los Angeles performance was supposed to mark the Good Girl singer's first since the end of her Reflection residency in Las Vegas.
The songstress shared a sentimental tribute to her fans earlier this week in honor of her final show. They are not to fret, though, as she's leaving her residency to go on her long-awaited Denim and Rhinestones tour.
The singer's sons supported her through the end of Reflection
Carrie also shared an adorable picture of how her two sons are supporting her as she departs Vegas. The picture is truly as cute as it gets, as it features Isaiah and Jacob giving their back to the camera, sporting matching black bomber jackets with the Reflection logo imprinted on it in gold.
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