Updated: March 17, 2020

Johnny Carson was remembered Monday on "The Tonight Show" with an affectionate look back at his nearly 30 years as host, including reminiscences from comedians and former guests that left many in the audience teary-eyed.

Carson died Sunday at 79 after nearly 13 years in retirement. NBC said he died of emphysema.

"As a performer, I never wanted to impress anyone more than Johnny Carson," said "Tonight Show" host Jay Leno, on his first show after Carson's death. "Johnny had that special quality of grace, charm and dignity in the public arena. He was an incredibly polite man and when you were invited into his house, this show, you knew you were an honored guest."

David Letterman, who competed with Leno to be Carson's successor and went on to success as host of CBS' "The Late Show with David Letterman," has also made it clear that the hole Carson leaves now is one that cannot be filled.

"It's a sad day for his family and his country," said Letterman upon hearing the news of Carson's passing. "All of us who came after are pretenders. We will not see the likes of him again."

"He gave me a shot on his show and in doing so, he gave me a career," Letterman continued. "A night doesn't go by that I don't ask myself, 'What would Johnny have done?' He has been greatly missed since his retirement. Thank God for videotapes and DVDs. In this regard, he will always be around. He was the best, a star and a gentleman."

Letterman had kept in touch with Carson and only a few days before he died, it was revealed that the comedic legend - rarely seen in public after his retirement - still enjoyed hatching headlines into jokes, some of which he e-mailed to Letterman for use on "The Late Show."

Onstage at the "Tonight Show" Monday, in tribute to Carson, were longtime Carson favorites Bob Newhart and Don Rickles, as well as comedian Drew Carey, singer k.d. lang and Carson's former sidekick, Ed McMahon.

McMahon told Leno that on their first "Tonight Show" together, he asked Carson what his own role should be. McMahon said Carson replied, "Ed, I don't know how I see my own role. Let's just go down and entertain the hell out of them."

McMahon also recounted the entertainer's strong sense of privacy.

"He was great with 10 million people, lousy with 10," McMahon said.

The tribute show contained an abundance of archival clips, including one of a dark-haired young Leno making his first appearance as a guest on the "Tonight Show." He would take over as host when Carson retired in 1992.

Others included Carson in one of his signature bits, the mind-reading "Carnac the Magnificent," a routine that David Letterman's band leader Paul Shaffer occasionally still borrows for the "Late Show."

Comedians Jerry Seinfeld and Roseanne Barr, who made their starts on the show, also appeared in clips.

Missing from the show was Carson's longtime bandleader Doc Severinsen, but he made an appearance on CNN's "Larry King Live," where he told King he was still grieving.

"I'm still having a problem with it, you know," he said. "I think 'I'm OK, now, OK, I've got everything under control,' and then bam, it hits again."

While the mood on the "Tonight Show" set was often celebratory, there was quiet reflection outside NBC's Burbank studios.

At Johnny Carson Park, adjacent to the studio, a vase of red roses and other flowers had been left at a plaque of the late-night host along with notes that said, "Goodnight Johnny, we'll miss you" and "Nobody did it better than Carson."

"He will be missed by a lot of people, especially his sidekick Ed McMahon," said Basha Kerbel, 73, of Toronto, who came with her husband and received standby tickets for the show. "It's a sad day for everybody. He was liked by so many people."

Debby Kulber, 50, of Cleveland, remembered Carson for his self-deprecating style.

"He was able to laugh at himself. And he made all the guests seem interesting," she said. "He was just very funny."

In Los Angeles, meanwhile, flowers were placed on Carson's star on the Hollywood Walk of Fame.

"This is a very sad day in Hollywood and I could tell you that Hollywood hasn't been this shocked since the news flash of Marilyn Monroe's demise," said Johnny Grant, the honorary mayor of Hollywood. "I think we all figured that Johnny Carson would just live on forever."