And the winner of 'American Idol' Season 17 is…

Last season on American Idol, judge Luke Bryan told Louisiana bayou boy Laine Hardy, “If you ain’t careful, you might win.” That didn’t happen; Laine floundered in Hollywood Week, and he went home shockingly early. But apparently Laine was less “careful” this year. He returned to the show supposedly just to play guitar for his friend Ashton Gill during her audition, but when the judges begged him to accept a golden ticket to Hollywood and give Idol another, more serious shot, he grudgingly accepted their offer.

On Sunday’s grand finale, Laine followed in the ($4,000 diamond-encrusted) footsteps of reluctant-but-successful past champions David Cook and Nick Fradiani — who also initially hadn’t wanted to try out for the show — winning the entire competition a year after Luke’s good-natured, if premature, warning/prediction.

“If you apply yourself and don’t get lazy, you’re gonna be one of the biggest stars on this planet,” Katy Perry further warned Laine Sunday. She later tweeted saying he’d be a superstar in “five years” — which seemed slightly shady, a backhanded compliment, since Laine’s two easy-breezy competitive performances Sunday had lacked the impact or ambition of the night’s more lavishly praised Alejandro Aranda and Madison Vandenburg. But Katy later more emphatically told Laine, after seeing him cover some Sam Cooke, “You are authentic. You’ve always been authentic. You weren’t ready last year. You are ready now.”

Laine may not have been ready for prime time in Season 16, but he triumphantly returned to Idol this season in style — literally, rocking slick designer suits, slicked-back Elvis hair, and shiny new teeth. And the newly confident 18-year-old lived up to his new slogan, “Party With a Hardy,” with a series of surprisingly swaggering, crowd-rousing, ’68 Comeback-style numbers. That slogan caught on so much, on Sunday’s finale he got to duet with country singer Jon Pardi, just so Ryan Seacrest could announce their double-billing as “Pardi with a Hardy.” (See what they did there?)

Laine, who won the real-time vote Sunday by singing Marc Broussard’s “Home” and Hank Williams’s “Jambalaya,” definitely wasn’t the most risk-taking artist of the top three (that would be runner-up Alejandro, who competed Sunday with two lovely original songs, “Millennial Love” and “Tonight”). Nor was Laine the best technical vocalist (that would be third-placer Madison, who belted power ballads by divas Kelly Clarkson and Lady Gaga and finally had her emotional breakthrough Sunday with “Shallow”). But he was undoubtedly the heartthrob of the bunch, and probably the most marketable. This guy’s going to sell a lot of records (and a lot of his new merch) and break a lot of hearts. And maybe he will be a superstar, and maybe it will take a lot less time than five years.

It’s an Idol cliché at this point to say a contestant would be better off not winning, but that might really be the case for an indie esoteric eccentric like Alejandro — since, let’s face it, no written-by-committee pop songs the Idol powers-that-be would have forced him to record for his Disney debut album would’ve been as cool as last week’s “Blesser.” The man has already pretty much released a stellar seven-song EP over the course of this Idol season. If Alejandro ends up getting his own record deal — on his own terms — then Season 17 might end up with two winners, for all intents and purposes.

Sunday’s other big finale moment, besides the winner announcement, had to be totally robbed opera-singing top 10 contestant Dimitrius Graham, aka “the male Beyoncé” — who would have done “Bohemian Rhapsody” if he’d made it to this season’s Queen Night — finally getting to sing that rhapsodic, operatic classic with Adam Lambert (who also crooned his vibey, velvety Velvet solo single, “New Eyes,” all dolled up in a David Johansen velvet suit). Is this the real life or is this just fantasy, indeed.

Other finale highlights included totally robbed top six contestant Jeremiah Lloyd Harmon dueting with Katy on a lovely “Unconditionally”; blind contestant Shayy reprising her “Rise Up” audition song hand-in-hand with Andra Day while a tearful Lionel looked on; stankfaced top 10 showman Uché spectacularly getting his groove on with Kool & The Gang to “Hollywood Swinging”; and Stevie Nicks’s prediction that Alejandro would go on to play with orchestras actually coming true, as he performed his goosebump-raising Hollywood Week original “10 Years” accompanied by a woolly-hatted symphony. In the finale’s most touching moment, a Pomona children’s choir sang Alejandro’s composition “Out Loud” and reduced him, and probably everyone watching, to tears.

Noticeably not performing was last year’s winner Maddie Poppe, despite the fact that her debut album Whirlwind, which she very briefly plugged during an awkward interview segment with Ryan Seacrest on the finale, had dropped just two days earlier. Seriously? This three-hour episode had room for Weezer’s cringeworthy ‘80s medley with Wade Cota and Walker Burroughs, and for Montell Jordan goofing around with Margie Mays, the “Country Justin Bieber,” and a dance troupe of mom-jeaned Katy lookalikes ... but no love for the reigning champ? Hopefully Laine won’t get the same brush-off next season.

Read more from Yahoo Entertainment:

• Don't stop him now: Adam Lambert returns to 'American Idol' to mentor Queen Night

• Katy Perry hilariously ugly-cries during surprise 'American Idol' marriage proposal: 'Why won't someone love me like that?'

• 'American Idol' contestants wear goggles in show of solidarity for blind contestant

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