It was October 2011 and Fili was fighting in Sacramento on a Capitol Fighting Championships card that was held in Urijah Faber's Ultimate Fitness gym, the home of the renowned Team Alpha Male MMA camp.
Fili won a unanimous decision in the ring over Tony Rios, only to see a group of his friends brawling with a contingent of Rios supporters in the crowd.
"I jumped out of the ring and got involved," Fili recalled. "I almost got suspended by the (athletic) commission."
He landed on the judge's table and headed for the brouhaha before fellow fighters Justin Buchholz and Danny Castillo dragged him back to the ring "kicking and screaming."
"It kind of made me realize that what I was doing was not the right thing to do at that time," he said.
Fili (13-2) has fought nine times since, winning eight of them, and is a member of Team Alpha Male.
On Saturday night, the 24-year-old featherweight looks to set the table for training partner Chad (Money) Mendes at UFC 179 in Rio de Janeiro.
Fili takes on Felipe Arantes (16-5-1 with two no contests) in the prelims before No. 1 contender Mendes (16-1) faces champion Jose Aldo (24-1) for the 145-pound title.
Fili has looked to keep a busy calendar since he was turned down for the cast of "The Ultimate Fighter." He was 4-1 at the time and was told he wasn't experienced enough.
Fili proceeded to win six fights in the span of 10 months in 2012.
He had been sidelined for a year prior to the Rios fight, injuring his knee in a 2010 loss to Derrick Burnsed. Fili met Faber, a former WEC champion, backstage and was invited to his gym.
It was a tough year for Fili. In addition to suffering his first loss and needing surgery, he crashed his car and got arrested.
His new training base was a step in the right direction, although it was painful at times as he made the transition from a small local gym to elite camp.
"I went from training two or three times a week and being the man to getting my ass kicked two or three times a day," he said. "It was a rough transition. I was still kind of partying and doing the wrong things. It took a while to transition, to see what everyone was doing. All these guys were making fighting a lifestyle. Once I started doing that, making changes outside the gym, it really started paying dividends."
When he first came to Faber's gym, he was under house arrest (for getting into a fight) and wearing a monitoring device on his ankle. He told his probation officer that fighting was his job, so he got to come to the gym to work out.
"I had to train with my ankle monitor on so I didn't throw left kicks for about thee months."
Fili had a tough upbringing and had to turn his life around. He credits MMA and Team Alpha Male for helping him do it.
"It definitely could have gone a lot worse," he said of his life. "It was actually going a lot worse, it was already headed the wrong way."
A lot of people like to fight, said Fili.
"But there aren't a lot of people who get their ass kicked and then go home and stick to their diet and give up going out so they can get rest. And then wake up the next morning and do it all again."
Fili won his UFC debut, stopping Jeremy Larsen in the second round at UFC 166 last October on two weeks notice. He was training for a welterweight fight (170 pounds) when he got the offer to fight at featherweight (145).
Fili was 178 pounds when he got the call for the fight. After a crash weight cut, he could get no lower than 148.5 pounds. The UFC appreciated his efforts, not to mention the win.
Last time out, against an opponent who was a step up in class, he was submitted in the third round by Max Holloway at UFC 172 in August.
"I learned body kicks hurt really bad," he said of the Holloway loss during which he absorbed several spinning back kicks.
"One of them, I felt his heel in my liver," he recalled. "And I almost sat down."
He wasn't the same after and Holloway took advantage.
Fili went back to the drawing board and says he just wants to "to kick some ass" in Brazil and show he belongs with the division's top fighters.
A colourful character who sings in punk rock bands, likes comics and tattoos and is sponsored by a local skateboarding shop, Fili wears tape on his earlobes in the cage to cover up holes stretched by spacers. A fan of body modification, he has eight piercings including his ears.
"They can be a pain in the ass at training but you get used to it," he said.
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