Guess the competition really is starting to heat up. On Monday night's live taping of The Voice, the remaining 12 contestants, their four coaches and an entire studio audience felt the full impact of L.A.'s heat wave -- but it was the evening's electric performances that ultimately nabbed the spotlight.

"If it reaches a certain degree in here, the lights could go out," host Carson Daly said half-jokingly of the faulty air conditioning. While Blake Shelton, Adam Levine and Shakira tried to ride out the sweltering heat, Usher took matters into his own hands, stripping down to a black tank top that showed off his chiseled arms at one point, prompting the other coaches to make fun of him for showing off.

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One staffer used a large black folding fan to keep Shelton cool in his seat, and Shakira had her makeup and hair touched up from time to time. But luckily for the competitors, the coaches' attention stayed consistent though the air conditioning didn't.

Team Adam's Judith Hill and Amber Carrington were the standouts of the evening, ignoring the earlier shenanigans of the evening to close out the night. Hill, a former backup singer for the late Michael Jackson, has been a show favorite from the beginning, but on Monday night's show, she dominated the stage with a polished version of James Taylor's "You've Got a Friend."

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The towering L.A. native even played her own accompaniment on the piano as she crooned.

"You are totally in control of your destiny at this point," Usher said. (The R&B singer had put on his shirt following the air conditioning's return.) "Everything that you do, every deliberate move that you make is so key."

Texas-born Carrington, on the other hand, made her impact through a touching version of Martina McBride's song "I'm Gonna Love You Through It," which she sang as a tribute to her late mother in honor of Mother's Day.

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"You did Martina proud and even more than that to me, you did country music proud," Shelton told the singer. "You did Nashville proud. Even though you're not on my team as much as I hate to say it, Adam's got a star on his hands with you."

The remaining 10 contestants include Team Adam's Sarah Simmons; Team Blake's Danielle Bradbery, Holly Tucker and the Swon Brothers; Team Shakira's Garrett Gardner, Kris Thomas and Sasha Allen; and Team Usher's Josiah Hawley, Michelle Chamuel and Vedo.

This article originally appeared on The Voice: Usher Strips Off Shirt After Air Conditioning Breaks On Set