Taylor Swift, Sam Smith take charge at KIIS-FM's Jingle Ball

Taylor, Sam, Ariana, 5SOS -- the stars were out Friday night for KIIS-FM's Jingle Ball concert

Sam Smith stood onstage at Staples Center and recalled that the last time he was there, in January, he was watching the Grammy Awards ceremony – from “way, way in the back.”

Less than a year later, the British soul singer had returned to the downtown arena Friday night as one of the biggest stars of KIIS-FM’s annual Jingle Ball concert. And he did it only hours after being nominated for half a dozen 2015 Grammys, including album, record and song of the year, as well as best new artist.

Things, it’s safe to say, have moved quickly for Smith.

Yet he wasn’t alone at Jingle Ball. This sold-out pop extravaganza was packed with acts that were barely more than a blip last Christmas: pint-sized heartthrobs like Shawn Mendes and 5 Seconds of Summer, along with young women such as Iggy Azalea and Meghan Trainor, both freshly anointed like Smith by the Recording Academy.

Each took a different route to the top (or what resembles the top for now, anyway). Mendes built his following through the video-sharing app Vine, while Trainor's "All About That Bass" is an old-fashioned Top 40 radio hit -- the kind whose continued presence on KIIS-FM is the implicit quid pro quo for a 10-minute performance at Jingle Ball.

But all had been there long enough to know they want to stick around like the handful of veterans on the bill.

First among those was Taylor Swift, who opened Friday's four-hour show with a thrilling set of hits that demonstrated how dramatically she's changed since she emerged nearly a decade ago as a guileless country-pop naif. Back then, Swift's special sauce -- beyond her deep songwriting craft -- was her ability to connect with listeners who viewed the singer as one of them.

She maintains that bond today, but it's no longer about coming off as Everygirl; it's about collapsing the distance between fan and celebrity, which might be even more potent.

At Staples, Swift oozed pure superstar confidence in "We Are Never Ever Getting Back Together" and "I Knew You Were Trouble," complete with four-piece horn section. "Blank Space," about her reputation as a woman with "a long list of ex-lovers," was as savage as it was poised. And though she said she had laryngitis, the scratchiness in her voice only made "Shake It Off" sound more sly.

But Swift was most impressive in a radical reworking of one of her earliest (and most wide-eyed) hits, "Love Story," which she presented here as a darkly moody synth ballad -- precisely the type of chance every A-lister should use her position to take.

Pharrell Williams, another of the lifers at Jingle Ball, didn't try anything so risky as he rolled through breezy renditions of "Happy" and "Get Lucky," the 2013 Daft Punk hit he helped create. But the guy's charm was undeniable, especially when he brought out Gwen Stefani for an unannounced performance of their new song "Spark the Fire."

Other surprise guests at Jingle Ball included Ed Sheeran, who played "Thinking Out Loud" accompanied only by himself on electric guitar, and Big Sean and the Weeknd, both of whom joined Ariana Grande during her set of sleek, big-voiced R&B.

Among the newcomers, 5 Seconds of Summer and Charli XCX made the most forceful impressions with catchy pop songs happily corrupted by the noise and belligerence of punk.

Azalea, a white Australian rapper who's caught flak for what critics call her clumsy appropriation of a black style, flashed a bit of aggrieved energy, as though she were ready to engage (or denounce) that critique. But it never fully materialized; in the end, her performance felt as toothless -- and as carefully self-preserving -- as Mendes' limp bedroom folk and Trainor's neo-bubblegum pop.

And then there was Smith, a beginner in fact if not in bearing. Singing his hyper-emotional retro-soul ballads -- songs about the desperate search for love -- the 22-year-old displayed a contradictory serenity that suggested he'd known all along he'd wind up where he has.

Even as he described how his romantic dalliances "never seem to go to plan," you could picture the tidy progression of his musical career: from a cheap seat at Staples to the arena's stage to -- as we're almost certain to see in February -- two arms full of gold trophies.

Twitter: @mikaelwood

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