Ben Affleck As Batman: Joss Whedon Says Actor Will 'Crush It'

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The "Avengers" helmer is throwing his support behind the star, whose casting has prompted petitions from fans.

Joss Whedon might be operating in a rival superhero-verse, but the Avengers helmer had nothing but kind words for newly named Batman, Ben Affleck.

"Affleck'll crush it," Whedon tweeted Friday evening, just over 24 hours after news broke that the Oscar-winner would be joining Henry Cavill in Warner Bros.' Man of Steel sequel. "He's got the chin -- just needs the material. Affleck & Cavill toe to toe -- I'm in."

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Whedon's words of support come following an outcry from fans, with many signing a petition calling for Warner Bros. to recast the part.

The studio announced Thursday that Affleck had been cast as the next Caped Crusader, with Man of Steel director Zack Snyder proclaiming: "I can’t wait to work with him."

In a statement, the director said that "Ben provides an interesting counterbalance to Henry's Superman. He has the acting chops to create a layered portrayal of a man who is older and wiser than Clark Kent and bears the scars of a seasoned crime fighter, but retain the charm that the world sees in billionaire Bruce Wayne."

The as-yet-untitled superhero film is set for a July 17, 2015, release.

Whedon is hard at work on Disney and Marvel's upcoming Avengers sequel, Avengers 2: Age of Ultron, due out May 1, 2015.

Twitter: @SophieSchillaci