BROOKLYN – Gregor Gillespie swore he would never compete again after years of suffering on a mat.

Gillespie (12-0 MMA, 5-0 UFC), who at UFC on ESPN+ 1 faces Yancy Medeiros (15-5 MMA, 6-5 UFC), liked to say he’d served his time in the prison that was the wrestling room. So when a friend declared over beers that he’d be good at fighting, his response was, “Shut the (expletive) up.”

They were watching Frankie Edgar, a local guy of sorts and ex-UFC lightweight champion, and Gillespie said he would never fight. Two and a half years later, he was sober and back on the mats.

Jordan Burroughs was the catalyst for Gillespie’s retirement from wrestling. He figured he’d never defeat the folkstyle master form University of Nebraska, and turned out to be right when Burroughs won an Olympic gold medal. But his love for alcohol didn’t kill his love for the sport.

Edgar was more of a signpost than a catalyst for Gillespie’s MMA career. He was teaching private lessons at a gym, a side gig as a wrestling coach at Hofstra University, when a fighter asked him to spar. Shoot takedowns, he was directed. The fighter spent a lot of time on the mat.

“I was like, ‘Oh my god, I could do this,’” Gillespie told MMAjunkie Radio.

Little by little, Gillespie immersed himself further in the world of MMA, taking classes on the side. He was good, as his friend predicted. One year in, he decided to quit his coaching job and pursue fighting full-time.

The rest is history, as they say. Gillespie remains undefeated after 12 professional fights, five of them in the UFC’s octagon. Medeiros marks a steep uptick in competition, a veteran fighter that could help him break into the top-15 in the crowded lightweight division. The two meet on the ESPN+ streamed main card of Saturday’s event at Barclays Center.

Gillespie won’t discuss anything about the fight. He refuses to talk about his opponents, as he did back in his wrestling days. Actions are his words, and he has yet to take them.

Gillespie isn’t completely resistant to change, of course. There will be a time when he’ll need to speak up. But some promises he keeps.

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