Rachel Bilson Cheers On Her Former ‘O.C.’ Costar Mischa Barton on ‘Dancing With the Stars’

Summer loves Coop! Rachel Bilson was one of many to sit down and watch the season 22 premiere of Dancing With the Stars on Monday, March 21. She gave a cute shout-out to contestant Mischa Barton, her former O.C. costar, via Instagram.

"Got to give it up for @mischamazing takes balls," Bilson, 34, captioned a screenshot of Barton, 30, and her pro partner, Artem Chigvintsev, on the TV. "Get it guurrrrlll!"

Got to give it up for @mischamazing takes balls. Get it guurrrrlll! ❤️

A post shared by @rachelbilson on

Despite the support, Barton received the third lowest score of the night. The actress, who admitted during rehearsals that she was nervous to take the stage, was given a 16 out of 30 for her tango. Returning judge Len Goodman said that it was like she was walking instead of dancing, which Barton considered to be a "harsh" critique.

Mischa Barton and Rachel Bilson
Barton and Bilson during a Chanel Fall/Winter party in 2005. Donato Sardella/WireImage

Nevertheless, Bilson appears to be a devoted fan. The Hart of Dixie alum and Barton played Summer Roberts and Marisa Cooper, respectively, on the beloved Fox series The O.C., which ran for four seasons from 2003 to 2007. Barton exited in season 3, however, when her character was killed off. (Cue "Hallelujah" and Ryan Atwood's tears!)

Mischa Barton and Artem Chigvintsev
Chigvintsev and Barton on 'Dancing With the Stars' on March 21, 2016. Adam Taylor/ABC via via Getty Images

Watch Barton and Chigvintsev's DWTS debut in the video above!

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