Matt Damon Jokes He 'Roughed Himself Up' During Sex Scene With Julianne Moore (Exclusive)

The co-stars admit to ET that things got a little weird on set!

Matt Damon's latest sex scene was more pain than pleasure.

ET caught up with the actor and his co-star, Julianne Moore, during a press junket for their new film, Suburbicon, where they opened up about the hilarious way they made their onscreen hookup look believable.

"We had a good ping pong scene together. That was not dull at all," he told ET's Carly Steel. "I actually bruised myself. Like, we realized the way the shot was, it looked like I was hitting her if I hit myself. And so I really let myself have it. I was spanking myself."

Moore confirmed this, explaining that Damon would hit, while she'd "yell."

"I like it rough," Damon joked. "I didn't realize how rough I like it. Then I got home and I was like, 'Wow.' I had one cheek that was completely discolored. Thank God I wasn't hitting Julianne..."

"The things you discover about yourself while acting, you know?" added Moore.

Damon continued on, explaining to ET that he and his wife, Luciana Barroso, actually have a ping pong table at home, so of course there were plenty of jokes about what happened on set.

"She was laughing," he recalled. "When she saw my butt, my cheek, she was alarmed. And then I obviously looked and I'm like, 'Oh, God. Oh God. Oh, that's from -- that was just from work, honey.'"

Suburbicon hits theaters on Friday. In the meantime, watch the video below to hear more on Damon's marriage!