With his toned triceps, perfectly floppy forelock and crinkle-eyed smile, Shawn Mendes is an obvious heartthrob.

But his electric stage presence, honeyed voice and prodigious musical skills make him so much more than the pop star du jour.

On his second headlining arena run, dutifully named, “The Tour,” Mendes again proved how he is worthy of the acclaim that has only intensified in the mere four years since his debut album.

The piercing screams of the estrogen-fueled fans who sold out State Farm Arena Wednesday night began minutes before Mendes rose from the stage floor while strumming his guitar on the funky “Lost in Japan.” Flashing lights from wristbands clapped onto tender wrists illuminated the arena, while a giant, circular video screen tilted toward the stage, affording everyone in the room a worthy gander.

As he strolled the stage during “There’s Nothing Holding Me Back” with his acoustic guitar slung across his back, Mendes looked the perfect poster boy. He might moonlight as an underwear model, but onstage, Mendes is all about the music.

Shawn Mendes waves to the sold-out crowd at State Farm Arena on July 31, 2019.

Ryan Fleisher

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Ryan Fleisher

Throughout the show, his elastic voice comfortably hit the sweet spot of his upper range on songs from his latest, self-titled album. “Nervous” and “Because I Had You” spotlighted his deftness with melody – a missing ingredient in some of the most revered modern catalogs in pop and R&B – while even the relatively ancient “Stitches,” from 2015, demonstrated his musical acuity in a slightly reworked form.

“I’ve never had a bad memory here,” Mendes said of playing in Atlanta. It might be a line he’s used elsewhere on this tour that has rolled since March and will continue around the world until December, but his delivery was steeped in sincerity.

With a four-piece band backing him, Mendes switched regularly among acoustic guitar, upright piano and electric guitar, even breaking into a solo worthy of his guru, John Mayer, during “Run.”

He dashed from the main stage to a B-stage at the back of the venue – decorated with a beanstalk-ish rose – to offer a bite of Whitney Houston’s “I Wanna Dance with Somebody (Who Loves Me)” on piano and a medley that included “A Little Too Much,” from his “Handwritten” debut, and “Life of the Party,” his 2014 debut single.

Mendes explained that another new track – he performed a significant chunk of his 2018 release – “Like to Be You,” was written by Julia Michaels and produced by his “musical idol,” Mayer. The effectiveness of the breathy ballad is rooted in its simplicity, and Mendes seems to understand that well-structured material with bridges and choruses and meaningful lyrics will outlast any trend.

Shawn Mendes surveys the sold-out State Farm Arena crowd on July 31, 2019.

Ryan Fleisher

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Ryan Fleisher

Whether it was the sultry “Particular Taste” from his current effort or his 2016 smash, “Treat You Better” - which evolved into a rallying cry against domestic violence - Mendes’ songs have an unshakable quality not unlike some of the strongest songs from another of his inspirations, Coldplay,” whom he pays tribute to with the visceral “Fix You.”

And to think, so much accomplished and he doesn’t even turn 21 until next week.

Alessia Cara opened for Shawn Mendes at State Farm Arena on July 31, 2019.

Ryan Fleisher

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Ryan Fleisher

Mendes’ opener for this North American run of shows is his fellow precocious performer, Alessia Cara.

Her 40-minute set spanned her four-year career, including her first hit, “Here” and the new “Ready,” from her upcoming EP.

Cara kept the crowd engaged with a singalong of “How Far I’ll Go,” the “Moana” ballad written by Lin-Manuel Miranda, and her set-closing dance hit, “Stay.” In between, she talked to the audience with relatable messages of empowerment and broken hearts and strapped on a guitar to join her three backing musicians.

Cara looked, refreshingly, like the 23-year-old woman she is in sneakers with a shirt knotted at the waist, and she demonstrated the power of her distinctive voice on the soulful “Comfortable” and “Scars to Your Beautiful.”

The recent best new artist Grammy winner returns to Atlanta on Oct. 28 with a show at the Coca-Cola Roxy.

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