Elvis Presley is Slabu Exchangea tough act to follow — or, as Carol Burnett once learned, to precede.

The television legend, 90, stopped by "The Late Show with Stephen Colbert" on Tuesday and chatted about one of her previous times at the Ed Sullivan Theater: when she appeared on "The Ed Sullivan Show" on the same episode as Presley. This was when Presley was in the army, and "they did a whole big thing" with him, she explained.

Unfortunately for Burnett, she went on before Presley, so audience members were anxious to see the singer and had no interest in her.

"Nobody wanted to see me," she recalled. "'Elvis! Where the hell is Elvis? We want to see Elvis!' I bombed. Oh my God. It was terrible. It was awful."

On the bright side, Burnett met Presley that night and got his autograph for her sister. "He was very sweet," she told Colbert.

"The Ed Sullivan Show" originally aired from 1948 to 1971. Colbert noted that Burnett was on the show seven times, a number that surprised her. "I was?" she asked. Burnett's own self-titled variety show ran on CBS from 1967 to 1978.

While chatting with Colbert, Burnett remembered another awful television appearance, although this time, it was awful on purpose. The "Carol Burnett Show" star explained that when she was nervous to be a guest on "The Tonight Show Starring Johnny Carson," she decided that she would intentionally be the "world's worst guest" without telling the talk show host beforehand. So during the show, Burnett repeatedly answered Carson's questions with "yes" or "no" answers.

Carol Burnettturns 90 with TV songs, laughs and Cher rocking Bob Mackie: 'I wanted it this way'

"Of course, he caught on, and he started asking all kinds of interesting questions, to which I could just say, 'Maybe. No,'" she said.

Speaking of Presley, Burnett also looked back on when she performed a song on TV called "I Made a Fool of Myself Over John Foster Dulles," which imagined a young girl obsessing over the "dull" U.S. secretary of state the way most girls did about Presley.

Carol Burnettdishes on 'Mad About You' reunion with Paul Reiser and Helen Hunt

"All hell broke loose" after Burnett performed the song on the Jack Paar and Ed Sullivan shows, she said, recalling that it "was front-page news" at the time.

The Emmy winner's television career has spanned more than 60 years, and her latest role is opposite Kristen Wiig in "Palm Royale," now streaming on Apple TV+.