For the second consecutive year, country-music princess Carrie Underwood came to the Twin Cities for a late-summer outdoor concert that featured none of the frills of her arena tours.

For the second consecutive year, it seemed as if Underwood were going to demonstrate that, despite all her Grammys and awards from various country music organizations, she is an overrated vocalist and entertainer.

However, late in her 100-minute concert Saturday night at the sold-out Mystic Lake Casino amphitheater, she stepped out of her showy but conviction-impaired, made-for-TV performance mode and cut loose. It was a Carrie-okie moment as the "American Idol" champ from Oklahoma threw herself, body and soul, into a medley of Aerosmith's "Walk This Way" and Guns N' Roses' "Paradise City." Her voice sounded harsh and dirty, her strut had noticeable swagger and the prim Barbie Doll suddenly became sexy. And she received the loudest reaction of the night from the 8,300 fans -- by far.

That blast of classic rock was the perfect setup for Underwood's own bashing signature, "Before He Cheats." After a night of rote he-done-me-wrong songs, you could finally see the rage in her eyes, read the anger in her body language and believe the growl in her voice. The ensuing and closing "Songs Like This" about what sparks tunes about outrage really made sense -- all sassy scolding, with little snippets of the suitably stormy "White Liar" by Miranda Lambert and "Single Ladies" by Beyoncé.

Before that four-song flourish, Underwood, 28, seemed like she didn't deserve to be mentioned in the same sentence as Jennifer Nettles, Lambert and Martina McBride, the top female singers on the Nashville charts these days. Underwood seemed more like a performer on autopilot than a heartfelt singer, selling the song but not feeling the emotion of her lyrics. As at the State Fair last year, Underwood tended to deliver nearly every number -- whether ballad or rocker, they're all about being wronged, unfulfilled or longing -- the same way. The only thing that seemed to set this apart from the grandstand gig was that she was uncharacteristically chatty.

Underwood gabbed about wearing a shredded sweater on an unexpectedly brisk night, blowing lyrics to "I Told You So" because her mind has only so much capacity, never winning anything until "Idol," shooting a video with Brad Paisley in 120 degrees in the desert (for "Remind Me," which she didn't play Saturday) and being out of breath because she was not in touring mode. Mystic Lake was one of only 11 live performances on her schedule in 2011 -- two others were the Grand Ole Opry and five are giant festivals. (She's busy working on her fourth album.)

But the appearance that maybe mattered most was performing a duet with Aerosmith's Steven Tyler on the televised Academy of Country Music Awards in April. Mentioning that duet Saturday clearly inspired her version of "Undo It," a song they did together. She also channeled her inner Tyler on "Last Name," her barnburner about getting drunk and waking up the next morning with a ring on her finger and not knowing her last name. Underwood proved on a sober Saturday night that, even at a booze-free casino, she's better when she plays it a little wild and loose.

Set list: Twitter: @jonbream • 612-673-1719