The last remaining country American Idol finalist will perform on Thursday night. Season 14 mentor Scott Borchetta tells Taste of Country that Maddie Walker still doesn't know what put her in the hospital for several days last weekend, but it wasn't a ruptured appendix.

That rumor was started by fellow contestant Savion Wright, who posted on Twitter that Walker's appendix ruptured last Thursday (March 12).

“That’s inaccurate, premature and trying to get more Twitter followers,” Borchetta tells Taste of Country, laughing.

That's not to say Walker's condition wasn't serious. She showed signs of illness during last week's rehearsal — at one point, she was completely laid out on her back, getting attention from medical staff. Everyone but Walker thought it was the flu, and she spent several days in the hospital receiving treatment and antibiotics.

“She still doesn’t know what it is," Borchetta says. "She’s still feeling a little bit weird but a ton better than last week. We really don’t know what it was, but there was something around her appendix that was irritated.”

Walker will perform on Thursday night. The theme is Movie Night, a repeat from Season 13. Borchetta says Walker has the advantage of being the only country contestant left on American Idol. If she's able to fully engage those fans, the 17-year-old from Iowa should go far.

Nick Fradiani is another finalist the 52-year-old Idol mentor is expecting to break out soon. He called him a "dark horse" that's "one of the best singers we have."

“You can feel that he is getting ready for a breakout performance and I think this week and next week will really determine the momentum that Nick has for the season.”

This week two-hour live episode of American Idol will air on FOX on March 19. Beginning next week (March 25), the live performances will return to Wednesday nights. NASCAR driver Jeff Gordon will visit the show this week. Legendary producer Nile Rodgers will co-mentor with Borchetta.

Every Wednesday, American Idol mentor Scott Borchetta will join Taste of Country to talk about that week's episode and the remaining finalists. 

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