Anna Kendrick failed to impress Ben Affleck with her pitch to play Robin in the upcoming Batman movie, but that's before the would-be Girl Wonder called in some back-up: Deathstroke.

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"True Blood" alum Joe Manganiello, who'll play the DC Comics mercenary in the Warner Bros. film, posted a photo of himself with Kendrick, accompanied by the caption "#Deathstroke and #Robin." Clearly, Deathstroke has Robin's back.

#Deathstroke and #Robin #MoheganSun20

A photo posted by Joe Manganiello (@joemanganiello) on

Kendrick jokingly floated the idea of playing the "plucky sidekick" to Affleck's Dark Knight during an interview with MTV promoting the new action thriller "The Accountant." She even donned a cape and mask, leading her co-star to reply, "Uh ... I'm not sure we're going to have a Robin."

Indeed, given the tone of DC's movie universe, it seems unlikely there's room for a living Robin. However, "Batman v Superman: Dawn of Justice" reveals the costume of the late Jason Todd in the Batcave, while a "Suicide Squad" Easter egg suggests Harley Quinn had a hand in his death.

Affleck will direct, co-write and star the Batman solo film, joined by Jeremy Irons as Alfred Pennyworth, J.K. Simmons as Commissioner Gordon and Manganiello as Deathstroke. No release date has been announced.

Manganiello will actually make his debut as Deathstroke next year in director Zack Snyder's "Justice League," appearing alongside Affleck, Henry Cavill, Gal Gadot, Jason Momoa, Ezra Miller and Ray Fisher. The film opens Nov. 17, 2017.