Mischa Barton Shares Behind-the-Scenes Rehearsal Photos Ahead of Her 'Dancing With the Stars' Debut

Eyes on the prize! Mischa Barton is back in the spotlight ahead of her big debut on season 22 of Dancing With the Stars, and the O.C. alum has been sharing numerous behind-the-scenes photos of herself rehearsing since the cast was revealed last Tuesday, March 8.

"Dance your heart out!" the millennial icon, 30, wrote last week, alongside a picture of herself in workout clothes. "Literally! 10 days left & freaking! Ahh @theartemc @dancingabc (this dance floor is dirty)."

Starting Monday, March 21, Barton and her dance partner, Artem Chigvintsev, will face a slew of new competitors including Fuller House actress Jodie Sweetin and Pittsburgh Steelers wide receiver Antonio Brown — and (surprise!) the friendly rivalry has started.

"@antoniobrown84 your my biggest competition!" Barton wrote on Tuesday, March 15. "Those moves! I love them ❤️ play fair ;) a girl gotta tango."

@antoniobrown84 your my biggest competition! Those moves! I love them ❤️ play fair ;) a girl gotta tango

A photo posted by Mischa Barton (@mischamazing) on

To prepare for Barton's big return to primetime television, her pro partner, Chigvintsev, 33, has pushed her to work on her posture and more. "Artem making me work on that posture @theartemc so I grabbed that mirror ball trophy for practice ;) @dancingabc 🔮 #closeenough ✨"

While it's been an eventful few weeks for the star, Barton took a moment this weekend to reflect about her upcoming journey and gave herself a personal pep talk. "Breathe relax & do it," she wrote alongside one black and white BTS pic. "I'm so lucky for the people in my life. No shout outs though. That's private. ok I might give a few in coming weeks."

hey guys we need a team name #helpus!! The crazier the better! Something strong! @theartemc @dancingabc

A photo posted by Mischa Barton (@mischamazing) on

Season 22 of DWTS debuts on Monday, March 21, at 8 p.m. ET on ABC.

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