It’s Leslie Smith’s personal policy to avoid combat in uncontrolled environments. She believes violence is a destructive force unless harnessed and used for positivity.

Smith saves hers for the gym or the cage, where she is known to fans as the woman who wanted to fight despite a mangled ear.

When she sees violence against woman, though, she’s got a history of making an exception. She once broke a man’s nose in Hawaii after she saw him slap his girlfriend.

So when a young man groped one of her friends this past month on a night out in San Francisco, she would not let it pass. And soon, she found herself in the middle of a fight.

Smith (7-6-1 MMA, 1-2 UFC), who competes in the women’s bantamweight division, had just arrived with friends, one of them fellow UFC fighter Heather Jo Clark, at The Mint, a karaoke bar. The group was sober. Everyone was deciding the next move when the man cut through them and grabbed Smith’s friend’s butt.

Smith caught up to him: Hey, you can’t do that.

“I can do whatever I want,” she remembers of his reply as he continued to walk.

Smith followed, insisting, no, he could not. Behind her was Clark, who sensed impending conflict and followed her friend. She figured Smith might also need a hand.

“We both have bum knees, and she’s just coming off a meniscus tear,” Clark told MMAjunkie. “So we’re both not in sparring shape, but I wasn’t about to not be there for her.”

The man, described by Smith as a “not very impressive” white male in his 20s or 30s and “just nasty,” according to Clark, stopped in his tracks. But rather than issue an apology, he spit at Smith.

Then, he threw a haymaker.

Instinctively, Smith ducked. She reached out and grabbed onto the man. In response, he grabbed her hair and pulled her sweatshirt over her head. She pulled away and freed herself, but again he got ahold of her hair again when she reengaged.

A thought popped in: She hadn’t drilled hair-pull defense.

“I’m not walking around saying I’m a big badass, but it is part of my identity to think that I am somewhat prepared for most fighting situations,” Smith said. “So when I didn’t have an immediate response, I was super bummed about that.”

On the bright side, Clark had her back. The veteran of “The Ultimate Fighter 20” delivered a soccer kick to the man’s groin, figuring it the quickest way to hobble him.

Smith drove the man into a wall, her hair caught in the man’s grip, and forced him to the ground with a double-leg takedown. As he turned his back, she wrapped her arms around his neck and began to get in position for a rear-naked choke.

Then, another thought: What now?

She didn’t want to re-injure her knee. She also remembered Eric Garner, the 400-pound asthmatic who was asphyxiated by a police officer in New York. A rear-naked choke is deadly force.

“I’m not going to kill someone for grabbing a butt,” Smith said.

Clark was a little less forgiving. She wanted Smith to choke him out.

But Smith released the hold, and she used a level of force with which she felt comfortable – she started elbowing the man as he turned to face her on the ground. He suddenly spoke up.

“I’m sorry.”

And…”I’m proud of you girls.”

“Then he put his hands into a prayer position and said, ‘Om shanti,’” Smith remembers.

Om shanti is a Hindu prayer for peace, often recited by yoga practitioners. The man repeated it over and over as they stood up. He had a shiner under one eye. By then, a crowd had formed.

Strangely, no one filmed the altercation.

After her adrenaline subsided, Smith felt ambivalent about the situation. On one hand, she felt proud that all of her training had been effective in the real world. On the other hand, she had violated her policy, again. She had fought an untrained civilian in public. Things could have gone a lot worse, for her or for him.

“I felt bad,” she said. “And then I realized that my purse was gone.”

Two weeks later, Smith taught her first women’s self defense class. You can guess what was on the syllabus.

“I have the sickest move for defense to hair-pull,” she said.

She didn’t to go public about the story, she said, but when her coach wrote about it on his Facebook page, prompting an outpour of support, she changed her mind.

She still thinks fighting outside the cage is a bad thing. But she might concede there’s a time when it’s the right thing to do.

Now, she’d like her purse back.

For more on the UFC’s upcoming schedule, stay tuned to the UFC Rumors section of the site.