Keith Urban has found himself a hot new duet partner! The country superstar invited Lauren Alaina to join him onstage at a recent gig in California, and the pair rocked the house with their surprise duet.

Urban and Alaina both performed at the California Mid-State Fair in Paso Robles, Calif., on Wednesday (July 26), and during Urban's set he invited Alaina to join him and sing the parts Miranda Lambert originated on "We Were Us," a duet between Urban and Lambert that was the second single from his Fuse album in 2013.

In the fan-shot footage above, which was posted to Instagram, Alaina brought a confident swagger and strong vocal performance to the song, dressed in knee-high black boots and a vest with a Kiss logo on the back.

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"We don’t get to do this song ever in our set, but I’ve heard Lauren sing it and I’m like, 'You’ve got to come out and sing this song with me,'" Keith tells the crowd in the clip. "So she said, ‘Ok, I’ll give it a shot.'"

The fans ate the performance up -- so much so, in fact, that Urban turned to social media after the show to post a video thanking them for singing along "loud and proud" and adding, "It was magical tonight."

Urban got video-bombed by what looks to be one of his own daughters as he spoke into the camera, finally realizing she was behind him in the back seat waving and holding up her stuffed animal as he spoke, and struggling to keep from laughing as he finished his message.

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