Alex Preston and Jena Irene
04/17/2014 at 02:00 AM EDT
's Top 7 turned the tables on one another Wednesday night, with each competitor picking a song for another finalist.
even stopped by to tout her tour and serve as a pseudo-mentor and judge.
Jena Irene (sporting new Lea Michele
bangs) stole the night with her emotionally powerful rendition of "Creep" (chosen by Caleb Johnson so she could "turn it into a big, beautiful theatrical rock song"), which she did, earning a standing ovation from Keith Urban
and Jennifer Lopez
(clad in a backless, DayGlo yellow leather dress).
"You Jena-fy every song that you do," said Lopez. "You're gonna be here for the long haul."
"You are a phenomenal talent," said a hoarse Harry Connick Jr.
, who called it "unquestionably" the best performance of the night. "You did some major damage tonight."
Alex Preston sang "A Team" (chosen by Dexter Roberts based on his online audition of it), and his vocals earned lengthy cheers from the audience and all A's from the judges.
"You deserve that applause," said Lopez, while Urban said Preston has "signature things" about his vocals that always "turn it into an 'Alex song.' "
Johnson showed off a more contemporary side, rocking "Family Tree" (picked by Preston) – the first ever Kings of Leon tune on Idol
Urban said it was a "great choice" of song, Lopez was amazed at his maturity, while Connick liked the way Johnson "changed the melody up."
Johnson chose "Gravity" for C.J. Harris so he could "take people to church," and his soulful rendition won over Connick, who called it his "best performance to date," but Urban said it needed "more of an arc."
Dexter Roberts sang "Muckalee Creek Water" (picked by Harris for its "deep, bluesy tone"), and his performance earned mixed reviews.
Lopez liked the "darker quality" he showed but said he needs to push himself.
Connick was harsher, saying, "You didn't really do anything differently from the original vocal … I want to hear you sing other things than singing along with the radio."
Sam Woolf sang "Sail Away" (selected by Jessica Meuse to "help with his connection"), but Connick still called him a "work in progress" and Lopez tepidly praised, "I did feel you trying."
Meuse sang "Gunpowder & Lead" (chosen by Woolf because "she's a badass" like Miranda Lambert
), starting her rocking performance bathed in blue light, but ending it in the judges' harsh light.
Lopez said she was "off a little bit vocally in the verses" while Urban was more direct: "If you want to stay in this competition, baby, get centered, get serious and commit to that lyric."
Results air Thursday (9 p.m. ET) on Fox.