2020 American Music Awards: Justin Bieber, Shawn Mendes kick off AMAs; The Weeknd wins R&B album

LOS ANGELES -- Canadian-born pop stars Justin Bieber and Shawn Mendes kicked off the 2020 American Music Awards with a performance of their new duet "Monster."

The singers released the track Friday and the AMAs, airing Sunday on ABC, marked the first time they performed it together. The performance began with a stripped-down Bieber singing his recent hit "Lonely," with songwriter-producer Benny Blanco on piano, and "Holy," where background dancers wearing masks joined him.

Mendes, strumming his guitar, then appeared for "Monster," which featured the twentysomethings singing lyrics about fame and growing up as celebrities who attracted massive public attention.

The performance, like a good number of them at the AMAs, was recently pre-taped because of the coronavirus pandemic. But host Taraji P. Henson, who excitedly danced to a medley of songs, appeared live from the Microsoft Theater in Los Angeles. She joked that A-list celebrities were in the audience, including Beyoncé (a cardboard cut-out of the singer appeared in a seat).

And another Canadian - the Weeknd - is poised to have an all-star night: He's nominated for eight prizes and won the first televised award - favorite soul/R&B album for "After Hours."

"The last time I received this award it was given to me by the late, great Prince. And, you know, he's the reason I get to constantly challenge the genre of R&B and yeah, I'd like to dedicate this to him," he said.

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Later in the show, the Weeknd and Kenny G will join forces for a rendition of the pop star's hit "In Your Eyes." The Weeknd will also perform "Save Your Tears."

The show will also include performances by Billie Eilish, BTS, Megan Thee Stallion, Bad Bunny, Jennifer Lopez and Maluma, Dua Lipa, Katy Perry, Bebe Rexha with Doja Cat, Dan + Shay, Lewis Capaldi, Machine Gun Kelly, Lil Baby, Nelly and Bell Biv DeVoe.

The Weeknd and Roddy Ricch - also nominated for eight awards - will compete for the show's top honor, artist of the year. Other nominees include Bieber, Taylor Swift and Post Malone.

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Megan Thee Stallion, who released her highly anticipated debut album Friday, scored five nominations including a bid for new artist of the year. Six artists earned four nominations each, including Bieber, Swift, Lady Gaga, Bad Bunny, DaBaby and Doja Cat.

Nominees are based on streaming, album and digital sales, radio airplay and social activity, and reflect the time period of Sept. 27, 2019, through Sept. 24, 2020.

Don't miss the 2020 American Music Awards on ABC on Sunday, Nov. 22, at 8 p.m. ET/PT, 7 p.m. CT.