Hollywood actress Katy O’Brian revealed that she was repeatedly punched by Sydney Sweeney while filming boxing scenes for the upcoming biopic on legendary boxer Christy Martin—and surprisingly, she enjoyed it.

Speaking at the A24 premiere of Ari Aster’s ‘Eddington’ in West Hollywood, O’Brian, who plays a rival boxer in the film, said, “I got punched quite a few times. It felt good. It was great. It better read well on camera.”

The film stars Sydney Sweeney as Christy Martin, one of the most prominent female boxers of the 1990s. Known for her aggressive fighting style and trailblazing career, Martin’s life was marked by both triumph and tragedy—culminating in a shocking 2010 murder attempt by her husband.

For the role, Sweeney underwent a dramatic physical transformation, gaining 30 pounds and building serious muscle. “My body was completely different,” Sweeney told W Magazine earlier this year. “My boobs got bigger. My butt got huge. I was like, ‘Oh my god.’ But it was amazing—I was so strong, like crazy strong.”

O’Brian acknowledged that while it felt good to be punched, it was harder to hit back. “Even with the extra 30 pounds, I would still have 20 to 30 pounds on her, so it never feels good,” she said. “But she didn’t seem to care very much.”

In fact, Sweeney’s fearlessness stood out. O’Brian added, “I was just like, ‘Please, don’t break my nose.’ I had to do ‘The Running Man’ right after. She was like, ‘If you break my nose, that’s fine.’”

Christy Martin’s story is one of grit, glory, and survival. She fought professionally from 1989 to 2012, became the world super welterweight champion in 2009, and survived a brutal attempt on her life by her husband in 2010. He was later convicted of attempted second-degree murder.

The untitled biopic promises to showcase the raw intensity of Martin’s life, both inside and outside the ring — and judging by the physicality involved in filming, the fight scenes are shaping up to be as authentic as her legacy.