At the end of Thursday night's episode of American Idol (Fox, 8PM ET) two more finalists will be sent home. But first, all eight remaining singers will perform one solo song, as well as a duet with another contestant. Mentor Scott Borchetta admits he's concerned about the Tristan McIntosh and Lee Jean pairing.

Jean is sick, Borchetta tells Taste of Country. That won't help him, or her.

“He’s not one of the bigger voices on the show," the BMLG mentor says after explaining how some contestants are more stylists than pure vocalists. "Tristan is. Lee is really gonna have to step up if he’s going to stay on par with Tristan.”

Both are just 15 years old and will lean on each other throughout their version of "I Don't Wanna Miss a Thing." It could end up being the surprise highlight of the night, but if Jean struggles, there's always the potential that McIntosh could sound off, as well, thus hurting her in the longrun.

For a solo selection, the Nashville country singer will sing Martina McBride's "A Broken Wing," a song Borchetta says she's been singing since she was 11. This song choice was easier than last week's, he admits. The Friday before her March 3 performance he left run-through thinking she was going to sing Lady Antebellum's "Run to You," and he wasn't thrilled about it.

“We had a situation where we had two songs and it was like, ‘Tristan, neither one of these are really great. So you really need to go back and work.”

The next day, he says he heard she was changing and suggesting Vince Gill's "Go Rest High on That Mountain" as her selection. After seeing iPhone video of McIntosh singing it, Borchetta knew it'd be her best performance to date, and it was.

Trent Harmon and La'Porsha Renae are the frontrunners for the Season 15 title, and they'll be paired together on American Idol Songbook night. Look for the singers to share a mic for "See You Again," a song from the Furious 7 soundtrack. This is the moment Borchetta is most looking forward to.

“Some of them were afraid to sing with her, because she is so powerful," he says of the other contestants. "Trent’s like ‘I got this, we’re good.’”

Harmon exuded confidence last week singing "When a Man Loves a Woman." He spent the week prior working on his facial expressions, but Borchetta explains that they were trying to fix more than appearance issues. It was about getting him to use other muscles when he sings.

“It was more about getting him to relax, because if he’s doing all of that with his face to get his sound out — it was like ‘Dude if you can relax that, there’s even more sound that can come out inside you and it’s not so forced.’”

The remaining two duet pairings will be Sonika Vaid with Avalon Young, and Dalton Rapattoni and MacKenzie Bourg. The three lowest vote-getters will perform last, with judges getting a chance to save one. Borchetta admits that his opinion matters.

“There’s a little bit of a wink and a nod in there, for sure. Because I’ve spent time with them all week.”

“They (the judges) may ask a question.”

Taste of Country will talk to Borchetta each week prior to the Thursday night episode of American Idol. Check back Thursday mornings for insight and a preview of what to expect!

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