A group of teenagers who attacked a couple had no idea who would come charging after them to stop the assault.

Calgary's own UFC fighter, Nick Ring, who had just finished a yoga session and went to Starbucks to get a coffee, saw an assault across the street and he wasn't about to let it go.

Ring - a 33-year-old mixed martial arts fighter who is gearing up for UFC 149 in Calgary next month - was leaving the coffee shop at Mac leod Trail and 94th Avenue when he thought he saw a group of about 10 people beating up a couple to steal the girl's backpack.

"I did not like what I saw and I wasn't going to stand around and watch that happen. It was a crime and it was completely wrong," said Ring.

"I'm not going to let anything like that happen if I've got anything to say about it. Not a chance."

The girl was getting her hair pulled and being kneed in the face while the boyfriend was being beaten up.

"It was right out of a movie. They were holding him back and beating him up, as well," Ring said. "It was a really horrible thing to see."

Ring checked on the victims and, along with another bystander, started to chase what he called the "wannabe gangsters."

During the chase, Ring called police on his cellphone.

The pair was able to catch one suspect, and Ring says police caught another five or six people.

As Ring chased them, witness Mike Geswein recognized the mixed martial artist and went to comfort the victims.

"I told the kid that got attacked, 'Don't worry, he's a UFC fighter. He has your back,' " Geswein said.

Geswein and Ring said both victims were bleeding after the attack. The boyfriend had a large cut on his face.

EMS spokesman Adam Loria said one person was taken to a clinic for minor trauma. The patient was in stable, non-life threatening condition.

Police said it was not a robbery, but rather a fight between teenagers after one girl gave the other a dirty look.

Two teenage boys, ages 16 and 17, and a girl, 15, were charged with common assault. Due to their ages, police are not releasing their names.

The victims are 17 years old.

According to his UFC bio, the 185-pound middleweight Nick (The Promise) Ring has a black belt in muay thai, a brown belt in Brazilian jujitsu and has won Golden Glove kickboxing titles. He competed in Season 11 of Ultimate Fighter.

Ring said the suspects did not know who he was or his fighting background.

"It puts me in the position that I have the ability to help others when they need it. I was glad to be able to put my skills to use to help these people out," said Ring. "I think that would be a scary position to be in if you're witnessing that and feeling powerless. With all my training, I think I'm in a unique position to be able to handle myself against these kind of cowards."

He said he could have waited for police to show up, but didn't want the assailants to get away.

"They would have been long gone by the time the cops got there. If we hadn't actually taken that guy down, those guys would have been way gone."

smassinon@ calgaryherald.com

smassinon@calgaryherald.com

Twitter: @stephmassinon