(Cover) - EN Showbiz - Jordin Sparks went into "fangirl mode" when she saw the Backstreet Boys and New Kids on the Block perform together.

The 21-year-old R&B singer is the opening act on this summer's collaboration tour between boy bands Backstreet Boys and New Kids on the Block.

Last month the pop supergroup, known as NKOTBSB, performed on US programme Dancing with the Stars, and Jordin admits the performance made her revert to an adoring fan.

"I was such a huge fan of Backstreet and 'N Sync. I was totally one of those girls growing up that had every album. It didn't really hit me until I was at Dancing with the Stars the other day and they were there performing their new song with New Kids and I went into total fangirl mode. I was so excited. I was the first person to stand up," she gushed in an interview with AI Now.

The Backstreet Boys had a host of hits throughout the 90s and 2000s, while New Kids on the Block enjoyed the bulk of their main success in the 80s and early 90s, when Jordin was a little too young to be a big fan. That said, she is still aware of many of the best-known hits, and cannot wait for the tour, which kick-starts in Rosemont, America, on May 25.

"And with New Kids, I do know some of their songs and I'm really excited. I'm trying to prepare myself and buying all their stuff so I can know the songs and sing every word while I'm there," she smiled. (C) Cover Media