When Nonito Donaire fights Panama's Rafael Concepcion in Las Vegas on Saturday, the recent IBF flyweight champion will take the next step toward an American dream he started as a picked-upon 10-year-old in the Philippine province of Bohol.

After moving with his family from the Philippines to the working-class East Bay suburb of San Leandro, California, Nonito took the opportunity to reinvent himself. He decided to fight.

"I was a little snotty-nosed, big-eared kid who didn't believe that there was a tomorrow for me, and look where I am now," Donaire said while wrapping his hands before a recent workout.

Donaire (21-1, 14 KOs) has progressed up the list of the world's top pound-for-pound boxers while winning his last 20 fights. His fame is still in its nascent stages, both in his adopted home and back in the Philippines, yet his headlining spot atop the "Pinoy Power" card at the Hard Rock suggests promoter Top Rank expects the Filipino Flash to get a whole lot bigger.

After years of struggles to get fights and management, Donaire actively pursues every opportunity, switching promoters and trainers _ even when that trainer is his father. Although his relationship with Glenn Donaire Sr. collapsed along the way, Nonito is still chasing that first dream despite a few mixed feelings about the sport.

"I'm not a fighter," he said. "When I was growing up, I was very timid, shy, quiet. One time, my dad showed me (Arturo) Gatti fighting on TV. He said, 'Do you want to box?' I said, 'Hell, no!'"

Donaire learned about boxing from his father, who listened to fights on the radio in their simple home in the Philippines. The family survived on his mother's salary as a teacher and the meager profits from selling homemade candy. Meat and soda were rare feasts, and the kids often wore slippers and ragged clothes to school so they wouldn't wear out their nice shoes and shirts.

Shortly after the family moved to San Leandro, living in a tough neighborhood near East Oakland, Donaire's older brother, Glenn Jr., began collecting trophies from amateur tournaments, getting attention that proved irresistible to Nonito.

Donaire eventually fought in the 2000 U.S. Olympic trials, but lost to Brian Viloria _ now the IBF junior flyweight champion _ in a discouraging decision that nearly drove him out of the sport. After turning pro in 2001, he spent about five years simply scrambling to cover his training expenses, often fighting on short notice but still winning all but one decision, way back in his second pro fight.

"When I had a chance to sign with managers in the past, I would hear that Filipinos are just not marketable," Donaire said. "In boxing chat rooms, they would make fun of Filipinos, say that they couldn't break an egg. That really inspired me to work hard to prove them wrong."

Manny Pacquiao changed all that in recent years, and Donaire realizes the debt he owes to the Philippines' most famous man _ who once attended the school where Donaire's mother taught fourth grade.

"I train hard, but it's not as hard as Manny," he said. "He lives in a whole different world. I don't think anybody else is going to get to that point, but I'm going to keep working hard."

Fighting as a big underdog, Donaire won his title in July 2007 with a brain-bruising knockout of Vic Darchinyan, the veteran flyweight champ who had broken Glenn Jr.'s jaw nine months earlier. Donaire's final punch _ a gorgeous left hand thrown from his backstep _ knocked senseless one of the lower weights' toughest fighters.

Three defenses later, Donaire is ready to move up to 115 pounds and the challenges beyond, both in and out of the ring.

Donaire readily acknowledges feeling the immigrant's familiar split between two worlds. He considers himself Filipino first, yet his life is mostly in the Bay Area. He has trained for previous fights in the Philippines, where his celebrity attracts constant attention, but he prepared for Concepcion in the comparative anonymity of San Carlos.

"This is my home," he said, looking around the tidy gym. "I have a lot of friends out here. I feel at home here, but I'm proud to be Filipino. In the Philippines, it's like every day is vacation."

Donaire has formed friendships with the other two big names in Bay Area boxing: Oakland's Andre Ward, the 2004 Olympic gold medalist, and Robert Guerrero, the former featherweight champion from Gilroy. He has trained in the East Bay hills with Ward, whose father sometimes slipped Donaire a few extra bucks.

Things aren't as familial with Glenn Sr., who trains fighters in the Philippines. Though Donaire no longer speaks to his father by phone or even text messages, he claims they're on good terms when they're around each other: "My family is weird."

After years of waiting, Donaire seemingly can't slow down, even for his father. If he beats Concepcion, Donaire is determined to get fights with Fernando Montiel and Jorge Arce, the two biggest names at 115 pounds, before moving up, perhaps eventually to lightweight.

And after knocking out Raul Martinez in front of 17,000 roaring Filipinos in Quezon City in April, Donaire would love to fight in the Bay Area, where the Bohol boy's life first turned in this improbable direction.

"When I get out here, people are going to be sitting on people's laps," he said, wrapping his fists tight. "That's another dream of mine."