Johnson nearly loses his microphone while rocking "Sting Me," while Jena Irene and Alex Preston also have memorable moments

Credit: Ray Mickshaw/FOX/Getty

Just like Donny and Marie, American Idol‘s Top 6 were a little bit country and little bit rock ‘n’ roll Wednesday night.

Each contestant performed two songs, and the results were mixed for most, with judges’ comments varying as much as the song selection.

Birthday boy Caleb Johnson had the super save and magical moment of the night while rocking “Sting Me” when he lost his mic before catching it without missing a beat.

“Now that was some rock ‘n’ roll!” said a standing Jennifer Lopez about the performance, which earned roars from the audience. “You created a moment!”

Johnson completely changed gears by singing “Undo It” by Carrie Underwood, a performance that couldn’t top the first one for Lopez and Harry Connick Jr..

Jena Irene showed her rocker fangs with “Barracuda” to open the show, a “killer performance” that “set the bar high for everyone,” according to Keith Urban, while Lopez said she had “a real chance” to make the finale.

Irene’s country take on Underwood’s “So Small” didn’t disappoint either, as she gave Lopez “goosies” and prompted Urban to remark, “You’re everything that Idol has always been about.”

Alex Preston kept his guitar but dropped his indie persona with “Animal,” which earned his harshest critiques of the year, with Lopez saying that “something was missing.”

“But you get a pass because you’re so good all the time,” added Connick.

Preston got his mojo back, however, with a beautiful rendition of “Always On My Mind.”

“I feel very lucky to have heard you do that,” said Connick. “You’re an artist.”

Blushing birthday boy Sam Woolf earned screams galore for his perky version of “It’s Time,” which also gave Lopez goosies.

“I got goosies on that one. I haven’t got a lot of goosies this season,” she said, while Connick told him, “You’re really blossoming, man.”

Woolf’s country take on “You’re Still the One” had the judges commenting more on how cute he was (Lopez) and how crazy he drove the girls (Urban) than his voice.

Jessica Meuse was “Slick” singing “Somebody to Love,” which earned strong praise for her “fantastic voice,” though the judges urged her to have more freedom.

Connick called Meuse’s “Jolene” “strong and convincing,” Lopez said her voice was “magnificent,” and Urban loved her vocal but hated the “dark” arrangement.

C.J. Harris tried rocking “American Woman,” and earned nice remarks, although Connick continued to question his intonation, Lopez said it was “shaky in the beginning,” and Urban said he needed more attitude (though Urban misinterpreted the lyrics’ true meaning).

His country song, “Whatever It Is,” didn’t go over much better, with Connick saying simply, “It wasn’t your best performance” and hinting he needed luck to stick around.

Results air Thursday (9 p.m. ET) on Fox.