"I had to take everything I was taught and reverse it," Carano said. "In training in mixed martial arts, you're taught to keep all your emotions inside and then just exude it through your power. With acting, you bring all your emotions to the outside and pull back your power. It's kind of like opposite day."

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Under the direction of Olivier Schneider, the French fight coordinator credited in "Taken" and "Safe House," the scene (and a later "rematch" aboard a cargo plane) unfolds as a battle royale between two accomplished yet differently skilled combatants.

"We were very specific," said Schneider. "Michelle is not a professional fighter. She's a street fighter — she's just trying to escape and survive. Gina was a pro MMA fighter; she's supposed to play a cop with fight training. We were all on the same page to do something brutal and spectacular but realistic."

With the actresses' growing sense of camaraderie came a physical comfort level that compelled Rodriguez to take risks. On set, she began badgering Carano not to pull her punches.

"She was so adorable about it, like, 'Go for it! Give it to me harder!' And I was like, 'You don't want that,'" Carano recalled with a laugh. "'We have to work tomorrow.'"

In the end, Carano and Rodriguez take opposing positions on what the future of female film fighting may hold.

"It's a matter of time before it's a monotonous thing," Rodriguez remarked.

"I personally can take it so much further than that fight scene," said Carano. "If it was me going up against another athlete, that would be awesome because I could do so much more."