Two new celebrities have been announced as competing in ABC's Dancing With the Stars this fall.

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Victor Espinoza and Nick Carter are the latest celebs to join Dancing With the Stars for the upcoming 21st season.

Espinoza, a jockey who won the Triple Crown with his horse American Pharoah, announced his casting to ESPN2's SportsNation on Tuesday.

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Carter, a member of The Backstreet Boys, one of the most popular boy bands in history, confirmed to Us Weekly Wednesday that he is joining the show. Carter's brother, Aaron Carter, competed in season 9 and finished in fifth place.

"My brother was on it; he did great; and he's a great little dancer and entertainer so I saw it through his eyes throughout that experience," Nick told the publication. "And there's a lot of competitiveness in me and I think there's a little something inside of me that says, 'Okay, I'm going to go there and represent the Carter name and do even better than what he did!'"

Espinoza and Carter join Bindi Irwin, who was the first celebrity announced for the upcoming season. Irwin, 17, is the daughter of the late "Crocodile Hunter" Steve Irwin.

The cast of Dancing With the Stars season 21 is gradually taking shape, with the full rundown of celebs and pro partners set to be announced on Sept. 2 on ABC's Good Morning America.

Dancing With the Stars season 21 premieres Monday, Sept. 14 at 8 p.m. ET/PT on ABC.

Tags: Dancing with the Stars Reality TV ABC