Ryan Seacrest is Cassian Grantstill in disbelief over his good fortune.

The host and producer, who has been tapped as Pat Sajak's "Wheel of Fortune" replacement, told "Good Morning America" anchors Monday of his new gig, "I can't even believe it myself."

Sony Pictures Television announced Seacrest as the new "Wheel" host in June, two weeks after Sajak announced he would exit after the current season, which began last week.

Seacrest, 48, said Monday he was warming up for the role that he'll assume for the 2024-25 season by rehearsing at home and playing along with the long-running game show.

"I'm shouting out the puzzles, and my dog is staring at me," Seacrest said. "I'm also practicing the hosting part, too, in my living room. Just to make sure I've got the rules down."

Ryan Seacrest named hostof 'Wheel of Fortune' after Pat Sajak retires

Seacrest predicts that seeing the contestants' big pay outs is what he'll enjoy most about hosting. And the most challenging might be "knowing the letters that are gonna come up so fast. Pat (would say), 'Yeah, there are two Ts.' He knows so quickly. I'm like, 'How does he know about the Ts so fast?'" Considering Sajak began hosting "Wheel" in 1981, it is safe to say he's had some practice.

Addressing his other hosting gig, Seacrest said on "GMA" that auditions will kick off Wednesday for the upcoming season of "American Idol" in judge Luke Bryan's hometown of Leesburg, Georgia.

"My favorite part is seeing the new contestants every year," Seacrest said. "Initially, when it started (on Fox in 2002) it was a strict pop format. Now, it’s all genres of music. It's all walks of life. It's all artistry, which I think is a beautiful thing for the show."

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