Rest in peace, Don Rickles.

Jimmy Kimmel broke down in tears while paying an emotional tribute to his late friend Don during his opening monologue on Jimmy Kimmel Live! on Thursday, April 6.

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“This is not going to be our usual show tonight,” the 49-year-old star began, while holding back tears. “We lost someone that we and I love very much today, and I’m sorry if you’re hearing this right now for the first time, but Don Rickles passed away this morning.”

jimmy kimmel don rickles getty images

Jimmy and Don in April 2009.

“He was 90 years old. I know it sounds crazy to say he was too young, but he was, because he was youthful and funny and sharp and generous,” Jimmy continued.

“I was fortunate enough to — not only have Don on this show as my guest – but also to become close to him and his wife Barbara Rickles — which was a lot of fun for me,” he said.

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“I grew up in Las Vegas, so Don Rickles — even when I was a kid — was a very big deal. His name was on the marquee at the Sahara. Then you’d see him with Johnny Carson,” Jimmy continued, adding Don was “very sweet, thoughtful, and humble.”

“There’ll never be another Don Rickles, he’s probably the greatest talk show guest of all time,” he said.

The iconic comedian sadly died on Thursday, April 6 at age 90. According to TMZ, Don passed away from kidney failure at his home in LA with his wife of 52 years, Barbara, by his side.

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In his final interview before his death, Don exclusively told Closer Weekly that he had no plans to retire from showbiz despite his age. “Honestly, I didn’t realize it — all of a sudden I was 90,” he said. “The years skipped by quickly. When it happened, I said, ‘Where did the time go?’”

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