The "American Idol" top 10 had help from Usher on Tuesday night (March 30), when the theme was soul and R&B songs. The "Papers" singer provided some of the most precise, helpful advice in "Idol" mentor history, helping the finalists mold their onstage personas and giving crucial tips on reaching the audience that resulted in strong performances from Crystal Bowersox, Lee Dewyze and Michael Lynche and a comeback of sorts from Andrew Garcia.

The seeming front-runner, Siobhan Magnus, was star-crushed meeting Ush, impressing him with Chaka Khan's "Through the Fire" and getting some all-important advice on how to make an impression with her wardrobe. Wearing a black-and-white wrap dress with silver moon boots, Magnus looked much better than she sounded, though, struggling mightily all along to stay in key during the sensual ballad and even falling flat during a few of her signature soul wails.

Randy Jackson and Ellen DeGeneres said it was pitchy and clearly off, struggling to find a positive note on the performance. Kara DioGuardi chalked it up to nerves and said every performer is entitled to an off night. Simon Cowell was not so kind. "It sounded to me as if you'd run a marathon and you were singing as you were running out of breath," he said as the crowd booed. "You were so all over the place. ... You look all over the place tonight. ... It was by far your weakest performance." And, he added, he's a bit sick of the screaming shtick at the end of nearly every performance.

When cowboy Casey James strapped on his guitar for a bluesy take on Sam & Dave's "Hold On I'm Comin," Usher was digging the voice and the rock swagger. The song, which had never been performed on "Idol" before, had the appropriate bluesy grit, with James channeling former "Idol" champ Taylor Hicks' Ray Charles-like mannerisms and facial tics during a faithful run through the 1966 Stax label hit.

Ellen thought it was a bit generic and safe, even as Randy called it another hot night and loved what he deemed James' broad vocal range. In a shocker, Simon called it Casey's strongest week to date and said he was feeling the authentic vibe.

In his continuing tradition of covering songs by women, Michael Lynche chose the relatively obscure [article id="1635109"]"Ready for Love" by India.Arie[/article]. As he crooned the song, Usher noted how much women love a man who can play a guitar and sing but reminded Mike to make sure he's playing to the whole audience. Once again making it seem effortless, Lynche opened with a series of dramatic, breathy runs, slowly picking out notes on his acoustic while sitting on a stool behind the judges' table in the midst of the audience. As his voice rose to a higher register mid-song, Lynche showed off his powerful range without resorting to histrionics.

Kara had never heard the song before Mike chose it, but she said he artfully tapped into its emotion, and Simon felt it was the first live show where he could take Lynche seriously as an artist and where he really believed his performance.

Didi Benami went with the Jimmy Ruffin hit "What Becomes of the Brokenhearted," which made her well up with emotion, a stroke of honesty Usher recommended she tap into while performing, not after. Though worried that she might not be able to keep it together onstage, Benami gave a dramatic, jazzy interpretation of the tune while wearing a sparkling, floor-length dress, ending with a emphatic shout of "tell me, tell me!"

"It was like swimming in jelly," Cowell said, deeming it too over-the-top, old-fashioned and off melody. The whole thing fell flat for Randy, who felt the song never caught fire. Kara was left wondering if the singer/songwriter has lost her way and confused the audience.

Chances were good that "Teflon" Tim Urban was going to struggle with the theme, and he made it harder on himself by choosing Anita Baker's lush "Sweet Love." Usher wasn't feeling it, suggesting Tim picture the woman he loves in front of him as he sang. Leaning on his puppy-dog eyes, which he aimed right at the camera, Urban gave another shaky performance, turning the sensual ballad into an easy-listening trifle.

Last week, Simon called him "silly." This week, he said the song choice was so wrong it was like "a mouse picking a fight with an elephant." Randy called it pedestrian and flat, even if it was "mostly" in tune, and DioGuardi said he sucked all the soul out. As Urban laughed at the harsh critiques, Cowell threw up his hands, seemingly frustrated that Urban's voters would likely keep him in the competition no matter what.

Still looking to get back his early groove, Andrew Garcia chose Chris Brown's "Forever," and Usher finally took off his shades to urge Garcia to loosen up and really feel the lyrics. By turning the dance-floor jam into a string-laden acoustic-folk ballad, Andrew appeared to be taking another big chance.

This week, though, it paid off. Randy loved the rearrangement, Kara said he took a giant leap back in the right direction, and Cowell agreed that it was a great choice, even as he warned the soft-spoken singer that he continues to come off as a bit boring.

Katie Stevens chewed off a major one with Aretha Franklin's "Chain of Fools," sassing up the tune with a growling lower register and strutting across the stage while bobbing her head from side to side and snapping her fingers. Ellen wished for a more contemporary, younger song. Randy thought it was one of the best performances of the night, comparing her strong vocals to Christina Aguilera's, which Cowell thought was absurd and gave a thumbs-down to the cold, robotic performance.

Looking for his moment, Lee Dewyze went obscure with the Cornelius Brothers' 1971 song "Treat Her Like a Lady," rubbing his outlaw-rocker grit onto the tune. Usher was blown away by Lee's voice and told him to just believe in himself. The advice seemed to sink in, as Dewyze rocked the house with a strummy throw-down that highlighted his barroom gusto and finally displayed some hard-won confidence and star power.

"Unbelievable," Randy gushed, a sentiment Kara backed up, saying Dewyze completely made the song his own. "This was the night your life may have changed forever," Simon added.

Crystal Bowersox promised a big surprise this week, as she put down the guitar and took a seat at the piano. Singing Gladys Knight & the Pips' "Midnight Train to Georgia," as a sultry power ballad, Bowersox started out at the keys then hopped up mid-song to work the stage in black heels for another perfectly controlled, polished tour de force.

The panel loved how she switched it up at the piano and gave across-the-board praise, with Cowell saying the song choice was sensational and the vocal incredible, even as he faulted the distracting backing vocalist and warned BoSox not to stray too far from the signature style that has gotten her so far in the competition.

Rounding things out was high-schooler Aaron Kelly, who went with the "Idol" chestnut "Ain't No Sunshine" by Bill Withers, a classic Usher urged him to personalize by emphasizing the signature "I know, I know, I know" refrain. It was rough going at first, with some shaky vocals and awkward wandering around the stage, but Kelly began to hit a groove mid-song as he added some sandpapery soul to the iconic tune about romantic longing.

Nobody raved about it, and Simon said he's heard much better versions on the show in the past. Despite the lukewarm comments, Cowell guaranteed Kelly would be around next week to try it again.

Wednesday night's results show will have Usher singing his new single "OMG" and Diddy-Dirty Money performing "Hello, Good Morning" as the herd is culled to nine.

Who was your favorite of the top 10 performances? Share your comments and predictions below!

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