WATCH: Backstreet Boys Cover 'Thong Song'

BSBbarber

The Backstreet Boys joined The Tonight Show host Jimmy Fallon on Tuesday to perform Sisqo’s 1999 hit “Thong Song” in the style of a barbershop quartet.

AJ McLean, Howie Dorough, Nick Carter, Kevin Richardson and Brian Littrell showed off their harmonies while dressed in ragtime costumes.

Sitting down with Fallon, BSB also cleared up some myths about the group – including one about Canadian actor Ryan Gosling almost becoming a member.

“We used to live in the same apartment complex when he was doing The Mickey Mouse Club,” McLean recalled. “We were playing basketball like almost every other day. The group had started. I kept telling him how big this was going to be and he was like, ‘Dude, the New Kids already did it, this is never going to work, just shoot the ball.

“Cut to… he was wrong and it did work.”

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BSB also denied rumours of a rivalry with *NSYNC. "Those were guys following their dreams. We were following our dreams," Richardson said, "and that's all."

The group is promoting the extension of the DNA Tour, which includes shows at Vancouver’s Rogers Arena on Aug. 9, Quebec City’s Videotron Centre on Sept. 15, Montreal’s Bell Centre on Sept. 16, and Toronto’s Budweiser Stage on Sept. 18. Tickets go on sale Feb. 14.

Watch the Backstreet Boys cover “Thong Song” below: