American Idol Judges Share Thoughts on Arthur Gunn's Sudden Absence from Star-Studded Finale

Before announcing Chayce Beckham as the crowned winner of season 4, the American Idol finale was full of star-studded performances — but one familiar face was missing: Arthur Gunn.

During Sunday's grand finale of the ABC singing competition show, longtime host Ryan Seacrest announced that the season 3 runner-up would not be joining Sheryl Crow for a duet as previously announced and scheduled — and judges Lionel Richie, Katy Perry and Luke Bryan had some thoughts on the situation.

"We don't even know what happened," Richie, 71, told PEOPLE during a post-show interview.

"It's a spicy show," added Perry, 36. "It's a live 3-hour show and quite honestly we've had a very colorful season. Curveballs galore."

"It's not the first time we've had to operate on the fly," Bryan, 44, responded. "[Graham DeFranco] (a Top 16 contestant) was there to support Chayce so we're pulling him out of the crowd and we're like, 'Get up and sing with Sheryl Crow' and he was like, 'Hell yeah.'

A source close to the situation told PEOPLE that Gunn, who returned this season after winning this season's comeback competition, chose not to perform last minute.

Gunn has yet to address the reasoning behind his absence.

ABC

The singer's absence wasn't the only "curveball" this season faced.

On April, Top 12 contestant Wyatt Pike dropped out of the competition due to "personal reasons." One month later, Top 5 contestant Caleb Kennedy exited the show due to a leaked controversial video.

Despite the bumps in the road, the season came to a joyful end as Beckham was crowned winner of Season 4.

Throughout the season, 24-year-old Beckham — who first caught the attention of the judges with his audition of "What Brings Life Also Kills" by Kolton Moore and the Clever Few — has wowed viewers with his soothing pipes and heart-wrenching story of triumph.

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"I've gone through a lot of ups and downs," Beckham, a heavy machinery operator who has long battled substance abuse, said during his audition. "It's been quite the roller coaster. My whole life kind of flipped upside down and I moved back home with my parents."

On Sunday, the judges praised Beckham — whose original song "23" hit No. 1 on the country charts immediately after its release — for his growth thus far.

"Sometimes God has to turn up the volume on your life to see if you're listening," Perry told Beckham. "You're listening. Keep listening. Stay the guy from Apple Valley because your world is about to change."

"Watching your confidence, I can't imagine what you're going to look like in five years," added Bryan.

The three-hour finale was kicked off with a performance by Macklemore — joined by Top 3 Willie Spence, Beckham, and Grace Kinstler — and included performances by Luke Combs, Fall Out Boy and Fleetwood Mac's Lindsey Buckingham, Chaka Khan, Mickey Guyton, Leona Lewis, Alessia Cara, and Idol judges Perry, Bryan and Richie.