LAS VEGAS – Opulence surrounds Junior dos Santos in his suite on a top floor of the largest casino in the gambling capital of the world. His luxurious digs at the MGM Grand are symbolic of the startling transformation he's made in his life.

The UFC heavyweight champion grew up in humble circumstances in Cacador, a small town in southern Brazil, unaware of the riches that lay beyond the city's limits.

Now, more than a decade later, another poor Brazilian child has left his destitute surroundings for the bright lights of Las Vegas. Nine-year-old Breno Luis Ferreira de Carvalho arrived at McCarran International Airport on Wednesday with his mother, Simone, and his older brother, Pedro Gabriel, and checked into his own room at the MGM.

They are guests of dos Santos, the star of the show Saturday who will defend his title against Frank Mir at UFC 146 at the MGM Grand Garden.

Dos Santos befriended Ferreira at his gym in Salvador, Brazil, and granted his wish to watch the fight with Mir at cageside. The experience has been overwhelming for Ferreira.

"It's just so exciting being here," Ferreira said Wednesday upon his arrival. "Even to get to sit on an airplane was like a dream. I could see all things out of the window, big buildings and we were really high above them, flying like a dream. But I'm here to help Cigano [dos Santos' nickname] defend his title."

Dos Santos sees a lot of himself in Ferreira. As a boy, dos Santos was not particularly athletic and never gave a hint of what he'd become. When kids in the neighborhood would choose sides for a game of soccer or basketball, they'd pick dos Santos first because he was bigger than most.

"After they saw me play once, though," he said, chuckling at the memory," that changed. Then I was always [picked] last. … I was never any good at games, at [sports]."

Though he wasn't athletic, he was inquisitive. Dos Santos would wander into a dojo and pepper the judokas with questions about their sport. His mind was on overdrive, and he was filled with a curiosity that could not be sated.

[Related: Frank Mir writes that Junior dos Santos has only a 'puncher's chance']

His childhood memories were fresh this week as he prepared in the northeastern Brazilian city of Salvador to face Mir, a two-time former champion. Dos Santos, 27, trained with several other professionals at coach Luiz Carlos Dorea's Champions Gym in Salvador, and a ragtag group of local children hung out with them.

That in and of itself isn't unusual, because for more than two decades Dorea has kept the doors of his gym open free of charge. Dorea is a noted boxing and MMA trainer in Brazil, but his full-time job is as a crime investigator for the civil police.

He's worked on cases ranging from petty theft to rape and murder.

The one common denominator among the crimes, Dorea said, is drug usage. Salvador is Brazil's third-largest city, behind Sao Paulo and Rio de Janeiro. And though there is great wealth in Salvador, so, too, is there extreme poverty.

The gym is near one of the favelas, or shantytowns, a crime-ridden area in which few residents have a realistic hope of escaping. Dorea allows free access to his gym as a way to give kids an alternative to using and selling drugs.

One child in particular caught dos Santos' attention. Breno Ferreira has been as regular as the sunrise at the gym for a year. When school ends, Ferreira appears.

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