Had Alicia Keys kicked her piano bench to the curb?

It was eight songs into her set on Sunday night at Arco Arena, and by that time Keys had shimmied with her dancers, belted through “You Don’t Know My Name” and even taken a break while her back-up singers plowed through “Lady Marmalade.” All that was missing so far was something she’s best known for: playing the piano.

Had Alicia Keys kicked her piano bench to the curb?

It was eight songs into her set on Sunday night at Arco Arena, and by that time Keys had shimmied with her dancers, belted through “You Don’t Know My Name” and even taken a break while her back-up singers plowed through “Lady Marmalade.” All that was missing so far was something she’s best known for: playing the piano.

The “As I Am” tour is all about Alicia Keys the entertainer. It’s a chance for Keys to get liberated from the piano bench, show off some dance steps and sing without that pesky piano getting in the way. Think of it as the Alicia Keys extravaganza, with a 10-piece band and half-dozen dancers helping Keys unleash her diva-dom.

But all of that sensory overload stuff wasn’t nearly as captivating as this: Keys all alone on stage, poised at her baby grand and pouring into her songbook. It just took about a half-hour into the show for this to happen.

But the payoff was worth it, as she romped solo through the sassy blues of “How Come You Don’t Call Me” and sang in breathtaking, bittersweet tones in “Sure Looks Good to Me.” Keys’ woman-at-the-piano routine always rocks the house.

The Mother’s Day crowd swooned and clicked on their camera phones. It was a somewhat small audience of about 7,000, filling Arco to just about half-capacity. The low turnout was kind of surprising given Keys’ sales clout. Her latest album, “As I Am,” debuted at No. 1 and has since sold more than 3 million copies. Then again, spending upward of $120 per ticket was probably too much of a splurge for some, especially given gas and grocery bills right about now.

But those who plunked down for tickets were treated to an energized and well-oiled show. We’re talking more than two dozen songs jam packed into 100 minutes. It was the kind of Keys concert that was meant for making your ears ring, especially with a backing band that bordered on overblown.

At least Keys’ voice was able to project over it all. She had to cancel a couple of shows early in the tour due to vocal problems. And though her speaking voice sounded a little raspy, like when she was plugging the Keep a Child Alive charity, Keys’ singing was perpetually powerful and on point.

Her delivery in “How Come You Don’t Call Me Anymore” and “Butterflyz” was the kind that’ll blow your hair back.

Speaking of recent vocal problems, show opener Jordin Sparks (a.k.a. the Season 6 “American Idol”) sounded fine despite a well-publicized throat injury in April. So much for our girl not being able to sing again. Instead Sparks sang to a filling arena with an every-girl kind of charm. Sparks still doesn’t have the lung power of Kelly Clarkson, but it was better than having David Archuleta up there.

Fellow opening act Ne-Yo couldn’t boast any vocal injuries or an “American Idol” crown, but he still worked the crowd with smoothed out R&B. His set that was like slow-jam central, featuring a lapdance from one of his back-up dancers and such hits as “So Sick” and “Sexy Love.”

Neither of them can compete with Keys. She’s a triple-threat of talent: A pianist and singer who actually writes her own hit songs. And she can bust a few choreographed moves as well. But it’s her fingers dancing on the piano keyboard that truly carries the show.

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SETLIST

1. “Ghetto Story”
2. “Waiting for Your Love”
3. “Where Do We Go From Here”
4. “You Don’t Know My Name”
5. “Teenage Love Affair”
6. “Lady Marmalade” (performed by back-up singers)
7. “Heartburn”
8. “Sure Looks Good to Me”
9. “How Come You Don’t Call Me”
10. “Butterflyz”
11. “Goodbye”
12. “Prelude to a Kiss”
13. “Superwoman”
14. “I Need You”
15. “Wreckless Love”
16. “Diary”
17. “Tender Love” (Force M.D.’s cover)
18. “My Boo”
19. “Unbreakable”
20. “Like You’ll Never See Me Again”
21. “Go Ahead”
22. “A Woman’s Worth”
23. “Karma”
24. “The Thing About Love”
25. “Fallin’”
26. “No One”
Encore: “If I Ain’t Got You”