Luke Bryan and Lionel Richie Talk Katy Perry's Potential 'American Idol' Replacement (Exclusive)

Katy Perry is exiting 'American Idol' after seven seasons and her fellow judges are coming to terms with it.

Katy Perry's time on American Idol is quickly coming to an end — a fact her co-stars are all too aware of. 

"It's kind of like the clock's ticking, every episode's one more getting closer to the finale where obviously we won't be doing this together," fellow judge Luke Bryan tells ET's Denny Directo after Monday night's live show. "It will be an emotional night. We know that she's not gonna be here. But we've had a hell of a ride. It's been fun." 

Judge Lionel Richie would prefer not to think about Perry's exit after seven seasons, telling ET, "I can't talk about that because it's upsetting."

Richie wants Perry to know that despite her exit, there's always a place for her on the ABC music competition show. 

"She's built a great family here, and I told her she can come back anytime," he says. "She's got a baby and she's got a family, got new music, and it's going to be amazing. I'm pulling for her. I told her, 'If you need help on the road, Luke and I will be right there.'"

Live from Hollywood, the Top 20 take the stage again as host Ryan Seacrest reveals the 10 hopefuls America has voted to advance. Judges Luke Bryan, Katy Perry and Lionel Richie select the remaining four who will round out the Top 14. - Disney/Eric McCandless

Longtime host Ryan Seacrest echoed the sentiment that Perry could return to the show, saying, "We're gonna miss her. It's not gonna be the same without her, but she's asked to keep the seat warm."

As for a replacement for Perry, the judges and host are hesitant to throw any names out there, but that doesn't mean there aren't stars they've been considering. 

"I do have my eye on at least two," Richie admits. "I find myself going back and saying, 'Hey, Katy, what do you think about this? Hey, Luke, what do you think about this?' What we want is somebody with a sense of humor. Talent is talent, sense of humor is everything."

Bryan says he plans to leave the decision making up to the powers that be.  

"There's a couple names going around, but I wouldn't even… that is, I let the all-powerful TV people decide that," he quips. "Big shoes to fill. She's always been a big personality. Her personality is what made Katy, Katy. She's unique in that, only one Katy Perry."  

Katy Perry on American Idol's live shows. - Disney/Eric McCandless

As for Perry's take on her final episodes, she says they have "flown by." 

"I am always emotional on finale, but gosh when the finale comes, I better just tape the false lashes to my face," she says. 

She also explains her decision to leave the hit show. 

"I'm just trying to make space for other things," she says. "It's not like me ending this show means I'm going to go retire on an island, even though that would be fabulous. I'm gonna go to work."

New episodes of American Idol air Sundays and Mondays at 8 p.m. ET on ABC and stream the next day on Hulu.