Kieran Culkin punched Jesse Eisenberg in the balls, squeezed his breasts during “Adventureland” audition

"The way to my heart is through my nipples," Eisenberg joked of his "A Real Pain" costar, who he says has "tortured" him in the past.

Jesse Eisenberg is remembering the time his A Real Pain costar Kieran Culkin inflicted some, well, real pain on him. 

The actor, who also wrote and directed the new dramedy, recently recalled the time Culkin "tortured" him as part of his audition for a role in the 2009 film Adventureland. 

"So the first time I met Kieran — I actually did not remember until he reminded me a few weeks ago on a press thing — but basically I was doing this movie Adventureland and Kieran was coming in to audition for a part,” Eisenberg told host Seth Meyers on an episode of Late Night this week. "And so, arguably, I should've been the one in the comfortable position, because I was already cast."

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But Culkin was fully prepared to take some risks to try to land the role — including using Eisenberg as his personal punching bag. 

"Kieran's character was a character who was supposed to punch me in the balls every five minutes, and he did that in the scene and then he grabbed my breasts and he squeezed and turned them," Eisenberg said. "And the director [Greg Mottola] said, 'Oh! Stop! Oh! Oh! Stop!' and Kieran didn't hear. And so he just was squeezing them."

While other actors may have reacted unkindly to getting casually harassed for an extended period of time during an audition they were holding, Eisenberg was impressed by Culkin's gumption.

"I was just thinking, 'This guy is a genius,'" he said. "Because he was so comfortable in his own skin. He was so good, too, as an actor. He's so good and so brazen to do that in an audition. And so when I was thinking about who to cast in [A Real Pain], somebody brought him up to me, and I was unconsciously realizing, 'That guy is perfect.' And I didn't realize that why he was perfect is because he has tortured me in the past."

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Meyers then joked that Culkin had spoken Eisenberg's "love language" during that fateful but fortuitous audition.

"Exactly," Eisenberg replied. "The way to my heart is through my nipples." 

Culkin didn't end up getting the part in Adventureland, but the pair's decades-old awkward encounter sounds like it has the same chaotic energy shown in A Real Pain, which follows cousins David (Eisenberg) and Benji (Culkin) — who were close as children but have drifted apart in their adult lives — as they embark on a trip throughout Poland in honor of their late grandmother.

A Real Pain opens in limited theaters today. Watch Eisenberg recall Culkin's ballsy audition in the clip above.