Billboard Music Awards: Meghan Trainor and John Legend Perform "Like I'm Gonna Lose You"

Meghan Trainor was joined by John Legend on the MGM Grand Garden Arena stage for a performance of her hit "Like I'm Gonna Lose You" at Sunday night's Billboard Music Awards.

Dressed in a long, sparkly gown, Trainor was backed by a band as she sang the beginning of the slow track. Legend, donning a black suit, walked onstage midway. Toward the end of the set, the two singers jokingly danced to the beat of the song together.

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Trainor was up for nine awards, including top new artist and top Hot 100 song for "All About That Bass." Legend was nominated in seven categories, including top R&B artist, and won both top streaming song (audio) and top radio song for "All of Me."

Ludacris and Chrissy Teigen co-hosted the awards show, which took place in Las Vegas and featured performances by such artists as Britney Spears, Hozier, Van Halen and more.