Jimmie Allen returned to the American Idol stage on Sunday night (April 4), serving as a star duet partner and reminiscing about his own experience of trying out for the show. The country singer tried out for Idol and made it all the way to the Hollywood rounds back in 2011, but was eliminated just shy of making the show's Top 24.

Looking back, Allen has said that his time on the show was a huge learning experience, and he's even shared the clip of his elimination on social media as inspiration for others to take rejection in stride and never give up.

On Sunday night's Top 24 Solos and All-Star Duets episode, Allen was on hand to mentor two contestants who, as of this week, have made it one step further on the show than he did. Early on in the episode, he appeared alongside Idol contestant Alanis Sophia, offering her some words of encouragement before teaming up with her to perform A Star is Born soundtrack standout "Shallow."

"I feel like I tell everyone that wants to be a singer, Idol's one of the best ways to really assess your talent," Allen explained. "Mental toughness is super important on American Idol. Because if you get so wrapped up in how great everyone else sings, you can sometimes not deliver your best because you're worried about how great someone else is."

Allen also urged Sophia to make "Shallow," originally performed by Lady Gaga and Bradley Cooper, her own. "In order for Alanis to succeed, she just has to sing it -- like Lady Gaga never did it," he points out.

The country star knows a little something about making the song his own: He and Abby Anderson also cut a version of "Shallow" in 2019.

Allen and Sophia's powerful harmonies and emotional interpretation of the song brought Idol judges Katy Perry, Luke Bryan and Lionel Richie to their feet after their duet performance, but all three agreed that Allen's star power overshadowed Sophia onstage. Perry commented that she had been more impressed by Sophia's solo performance of Sia's "Alive" earlier in the episode, but she came across less confident in her duet with Allen.

"I think just get in that headspace to where you know you own the stage," Bryan added. "I mean, your voice -- now  you've got to build on that character, and on owning the stage."

Allen is due to return later in the episode when he mentors another Idol hopeful, Cecil Ray. American Idol airs on Sunday and Monday nights on ABC at 8PM ET.

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