"I actually did talk to him about it. I said, 'Don't do it.'" Clooney said.
In the latest episode of The Hollywood Reporter's Awards Chatter podcast, Clooney, who starred as the Caped Crusader in 1997's "Batman & Robin," said he offered advice to Affleck about playing Batman back when the two worked together on "Argo."
"I actually did talk to him about it. I said, 'Don't do it.'" Clooney said. "It was only from my experience, which is, you know...He did great, though."
He added, "After a few films and after the show -- what you don't understand is now they're using you...to greenlight films, so you have to think differently than just as an actor."
Although Arnold Schwarzenegger, who starred as Mr. Freeze in the action flick, had a much higher paycheck than Clooney, it was the now two-time Oscar winner who was hit with the most backlash from the film, which also starred Uma Thurman as Poison Ivy, Chris O'Donnell as Robin and Alicia Silverstone as Batgirl.
"Schwarzenegger was paid, I think, $25 million for that, which was like 20 times more than I was paid for it, and, you know, we never even worked together,” Clooney recalled. "We worked together one day. But I took all the heat. Now, fair deal; I was playing Batman and I wasn't good in it, and it wasn't a good film, but what I learned from that failure was, I had to rethink how I was working. Because now I wasn't just an actor getting a role, I was being held responsible for the film itself."
Despite Clooney's warning Affleck went on star in 2016's "Batman v. Superman: Dawn of Justice" and "Suicide Squad," along with "Justice League" in 2017. All three DC installments were railed by critics while performing decently at the box office, although below expectations.
Affleck announced back in February he had hung up the cape for good and was retiring from the role.
"I tried to direct a version of it and worked with a really good screenwriter but just couldn't come up with a version," he told Jimmy Kimmel. "I couldn't crack it and so I thought it's time for someone else to take a shot at it. They got some really good people so I'm excited."
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