TORONTO - Lady Gaga granted a 10-year-old Canadian a share of her spotlight on Thursday, inviting YouTube singing sensation Maria Aragon onstage for a duet on "Born This Way" in front of a roaring crowd at the Air Canada Centre.


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About midway through a nearly two-hour set, Gaga invited the Winnipeg grade-schooler on stage and the packed audience bellowed its approval. With an orange stuffed monkey slung around her neck, Aragon hugged Gaga tightly then sat on her lap at a black grand piano, taking the lead on vocals.

Aragon — who shot to Internet fame after a video of her performing Gaga's outsider anthem went viral and drew more than 17 million views — managed to remain perfectly poised throughout the performance. She then took the microphone to thank her family and friends in Winnipeg, as well as the enthusiastic Toronto audience.

"I just want to thank all of you for your support," said Aragon, clad in a black leather jacket, pink hoodie, sparkling black pants and a pair of high-top sneakers.

"I hope you enjoyed it."

Gaga, meanwhile, was less composed, even choking up following the duet.

"Maria represents what this song is all about," said Gaga, who was clad in a black leather bikini during the song. "It's all about the next generation and the future."

"Thank you for being here to witness such a beautiful girl," she added, before flubbing the introduction to her next song.

"See? She made me all nervous, she's such a superstar."

Aragon, who has been interviewed on "Ellen," "Good Morning America" and "Access Hollywood," had to stay up long past her usual bedtime on Thursday — Gaga didn't invite her onstage until well after 11 p.m. ET.

In fact, the crowd seemed restless before Gaga took the stage, even booing as a few Michael Jackson songs rotated through the house speakers.

But once she did emerge, the fans — or as Gaga calls them, her "little monsters" — seemed to instantly forgive the wait, roaring throughout the set-opening "Dance in the Dark."

From there, Gaga put in an energetic — and typically bizarre — performance, with everything fans have come to expect from the eccentric pop star: outlandish outfits, garish setpieces and, of course, impossibly infectious dance tunes.

The 24-year-old's debut record, "The Fame," spawned four Top 5 singles before reaching platinum four times over in the U.S. and seven times in Canada, where the singer has seemed to possess an even stronger stranglehold on the charts.

She referenced that support on a couple of occasions during the show.

"Thank you for shoving it up the rest of the world's ass," she said.

Indeed, even as the night wore on, the crowd betrayed few signs of fatigue, hopping along to the music.

Many looked the part, too, with dyed hair, imaginative costumes, brightly coloured wigs and facepaint commonplace. Some looked like they were going to a midnight screening of "The Rocky Horror Picture Show," defying the frigid weather outside with skimpy outfits suitable for Gaga's own wardrobe. One unself-conscious soul wore a bikini made of yellow caution tape.

But there's no topping the master — over the course of her set, Gaga appeared drenched in blood, covered her upper body and most of her face in a thicket of dark animal fur and, at one point, appeared nearly naked but for a nun's habit.

The plot of the show is loosely based around a journey to the "Monster Ball," where the characters will be set free. Originally, the stage was dressed to look like a decaying urban nightmare, while later it was adorned with spooky trees and a giant monster puppet.

At various points, Gaga took centre stage to preach about gender equity, gay rights, religion, lip-synching (she's against it) and even Barbie dolls.

"Barbies made me want to throw up my food in high school," she said, after biting the heads off a couple of the defenceless dolls.

"Tonight and every night after you can be whoever it is you wanna be."

Though there were many young kids in attendance, the show was pretty raunchy. Gaga sprinkled her stage banter with profanity, at one point bragged about the size of her (male) genitalia and danced as provocatively as possible.

Still, it ended on a sweet note, with Aragon returning to the stage for a second performance of "Born This Way."

She and Gaga strutted to the front of the stage and danced together, holding hands. Then the multiple Grammy winner and her dancers swarmed Aragon for a group hug and took a final bow, altogether.

Gaga's tour will wind through Ottawa and Montreal before wrapping May 6 in Mexico City.