We’ve been through this before, but it bears repeating: There are no encores at festivals. You don’t get to blithely say goodnight, leave the stage and wait for the audience to cheer you back on to play your mega-hit when you’re playing a tightly slotted hour-long set.

No one really believed that Camila Cabello was going to skip playing “Havana” at the Austin City Limits Music Festival, but for a moment it seemed like that might happen when she exited early and the crowd was too baffled to cheer riotously on Sunday night. It was a bit embarrassing.

But other than that (and inadvertently referring to us as “Dallas” once or twice), the 21-year-old pop phenom proved her stadium-packing potential in a 6:30 p.m. set on the big stage.

She made a rock star entrance, whipping her hair to pounding drums and power chords that gave way to the slinky ode to obsessive love, “Never Be the Same.” Then she demonstrated her range, segueing into the Latin rhythm-infused hit, “She Loves Control.”

Dressed like someone who clearly came of age during the sexy vampire phase of American teen film culture, Cabello performed with poise and confidence. Her voice was strong and while she let her six-person dance team do the heavy choreographic lifting, her moves were no joke.

One of her biggest strengths, the reason her star will continue to rise, is an ability to forge a connection with the audience. A huge crowd pressed toward the skyline stage to see her, yet she managed to create a sense of intimacy. She confessed to being a hopeless romantic and led a sing-along of the Elvis Presley classic, “I Can’t Help Falling in Love with You.”

Later, after playing the song “Scar Tissue,” she opened up. She said the song, which didn’t make it onto her debut solo album “Camila,” was written during the “most vulnerable, hardest part of my life.”

Speaking directly to the young people in the audience, she talked about her process of persevering through pain, of healing and recovering.

“You can’t escape pain. You can’t go around pain. You have to go through it,” she said. Then she reminded her young fans who might be feeling lost or confused to “be kind and be patient and be loving with yourself.”

Then she played an extended mix of “In the Dark” with a powerful a capella chorus.

Her dancers framed her songs with everything from breaking to interpretive modern dance, and the entire set was engaging, but the (somewhat awkward) encore was the obvious highlight. The crowd exploded for the Pharrell Williams-assisted hit “Sangria Wine,” and her sensual rendition of “Havana” created one of the best singalongs of the entire weekend.

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