Once upon a time, Blake Shelton invited Backstreet Boy AJ McLean to a private party to sing "I Want It That Way" with him. What the country superstar didn't know was the "Night Visions" singer once had a huge crush on his girlfriend, who was there watching.

It happened at a private party in Las Vegas, and Shelton actually sang the Backstreet Boys hit with the Backstreet Boy. The new duo followed Gwen Stefani's performance and actually closed the show. It was a little terrifying especially for McLean, because ... well, let him tell the story in the video above. It's an all new episode of Favorite Follows!

Taste of Country asked McLean to talk about who he follows on Instagram, and he named Shelton, Dug the Pug, Meghan Trainor and Dan + Shay (among others). "Big fan. Love these guys so much," he says of country music's "Tequila" duo. "They're fans of us and I was like, 'Wait, we're fans of you guys!'"

Could a Dan + Shay and AJ McLean or Backstreet Boys collaboration be down the line, maybe? At least one half of this party is all about it.

McLean is the latest singer to call out their Favorite Follows episode for Taste of Country, following Cole Swindell, Jimmie Allen, Morgan Evans and Dylan Scott who, as it turns out, has a huge man crush on a famous athlete. Watch more of those below.

"Night Visions" is McLean's latest country single after "Back Porch Bottle Service." Both are expected to be included on a studio project coming soon. The music video for "Night Visions" was released on CMT in October.

See More Favorite Follows Videos! 

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