Mike Brown always loved being a professional mixed martial arts fighter.

Brown, 39, is now embracing his new career as a coach at one of the world’s elite MMA gyms.

“It’s really like kind of a dream job. It’s something I would do for free,” said Brown, the assistant MMA coach at American Top Team in Coconut Creek, Florida. “If I was a billionaire, I would go to the gym and would help guys. I really love the fight game and I like working with high-level pro guys.”

The toughest part is admitting his own fight career is over. Brown’s last fight was Aug. 17, 2013, on a UFC Fight Night show at the TD Garden in Boston – a 50-second TKO loss to Steven Siler.

“Yeah, yeah, I’m retired,” said Brown, a Standish native and former state wrestling champ at Bonny Eagle High.

“I’ve never actually come out with it before. But I still go live a lot in the gym.”

The transition to coaching began while Brown was still fighting. He trained at American Top Team during his most successful years in a 26-9 pro career that included winning and twice defending the World Extreme Cagefighting featherweight (145-pound) title and five fights in the UFC.

Since his last fight Brown has worked with more than a dozen American Top Team fighters, some competing in the UFC.

“It is a big change,” he said. “I don’t really have a specific number of guys because the team is huge. Some guys I help a real lot. I probably work with 10, 20 guys but to different effects.”

Brown’s coaching could soon be on display for a national television audience. The new season of the UFC’s reality TV show, “The Ultimate Fighter” debuts April 22.

It will feature a real-life rivalry between two competing gyms: the Coconut Creek branch of American Top Team vs. The Blackzilians of Boca Raton, Florida.

UFC non-disclosure policies prohibited Brown or American Top Team General Manager Richie Guerriero from discussing any specifics about the show, including whether Brown would be involved. What is known is each gym put together a team of eight welterweights (170 pounds).

According to the UFC web site, training will take place in the fighters’ home gyms and bouts will be contested at both gyms.

In January, Brown talked about the dynamic between the two gyms.

“They’re a big rival team,” he said. “They’re the next town over. It’s a world-class gym like ours and it was started by some of our guys who left the gym” in 2011.

Often the opposing gyms’ fighters are pitted against each other on MMA cards. That was the case when one of Brown’s primary trainees, Charles Rosa, of Peabody, Massachusetts, claimed his first UFC win at the TD Garden on Jan. 18. Brown was in Rosa’s corner for his three-round decision win against Blackzilian fighter Sean Soriano.

“He’s not just a great coach but also a great mentor,” Rosa said. “Obviously his knowledge is unbelievable. He’s a former champion of the world and I really trust his judgment.

“He’s also a really great person. It’s comfortable to have him around. He eats when I eat and sleeps when I sleep. He really does have a love for the sport.”

Rosa, 28, is 10-1 as a pro (1-1 in the UFC) and is scheduled to fight Yair Rodriguez in Mexico City on June 13.

In the early stages of his MMA career, Brown was an assistant wrestling coach at the University of Southern Maine. He also moonlighted as an instructor in wrestling and MMA techniques at seminars for Portland-area police officers.

In 2005, knowing relocation was necessary to grow his career, Brown moved to Florida and joined the American Top Team. When not actively training for a fight, Brown’s veteran presence was a resource in the gym for aspiring fighters.

As recently as last summer, Brown was still holding out hope he could get back in the UFC cage. A potential April 2014 fight in Orlando, Florida, had been shelved due to neck problems. Then knee issues nixed Brown’s hope of getting on the UFC show last August in Bangor.

“Now I’m starting to think maybe (another fight) wasn’t meant to be,” Brown said at the time.

Instead of returning to Maine, Brown went to China as a coach with American Top Team fighter Colby Covington in his UFC debut (Covington won and is now 2-0 in the UFC).

“I was pretty sure I was done after my last fight but I just wanted to leave the door open just in case,” Brown said recently. “I didn’t want to keep flip-flopping because even now I say, ‘What if the right opportunity came open?’ “