With one eyebrow raised, coach Dennis Rodarte responded with an incredulous look. Rodarte had to chuckle. The nerve of Yanez. He recalls when a younger Yanez, who will turn 19 on Thursday, occasionally goofed off when the coach wasn't looking.

The coach can laugh now. No one questions Yanez's work ethic. Yanez, 5-foot-3 and a brick over 100 pounds, is on the U.S. boxing team after dominating the light-flyweight (106 pounds) division at the U.S. Olympic trials in August. As a captain of the national team, Yanez is one of USA Boxing's most promising athletes and the first American to win Pan Am Games gold in the light-flyweight division.

U.S. boxing officials hope Yanez can produce the first Olympic medal in that division since 1988, when Michael Carbajal claimed silver. Paul Gonzales was the last U.S. light-flyweight boxer to win Olympic gold in 1984.

Yanez can earn a berth in next summer's Beijing Olympics by finishing in the top eight at the world boxing championships that begin Tuesday in Chicago. He hasn't lost a fight in the United States in more than five years, compiling a record of 89-0. In the past three years, he's 26-3 in international competition.

"My goal is to finish in the top three (at worlds). In Beijing, the goal is No. 1, no doubt," says Yanez, who is ranked sixth in the world by ABA Boxing.

Going to China for his first Olympics is a realistic goal for the Duncanville, Texas resident. "Some guys are on the edge of falling short of qualifying," USA Boxing's director of coaching Dan Campbell says. "I don't think Luis is one of them. He is a young kid and occasionally wants to do it his way. But if he listens, he'll be fine."

Seeking structure

Bulmaro Yanez didn't intend for his son to become a standout boxer.

When Luis was 9, Bulmaro had trouble getting his son to listen and settle down. Another parent told Bulmaro about Rodarte, a coach who was firm but patient and made boxing fun. Bulmaro took Luis to Rodarte's gym so he could receive structure and release energy in a positive environment.

His long-terms goals for his son were the same as his short-term goals: keep Luis out of trouble and instill discipline.

"I wanted to make sure he was going the right way, not the wrong way," Bulmaro says, standing outside the Dallas gym where his son trains. "I told Luis, 'Your friends are in the gym. Your friends are not on the streets.' "

The coach asked for the father's help in training his new pupil. Rodarte instructed Bulmaro to throw out all junk food and soda. After looking at his cupboards and refrigerator, Bulmaro wondered if he would have any food left. But he complied, replacing the bad food with chicken breasts, vegetables, fruit and healthy snacks.

"I then asked Luis, 'Are you sure you want to box?' " Rodarte says. "He was gung-ho. He had that 'want' from the get-go. He'd go through a workout and ask me, 'What's next? What can I do now?' He was one of those kids.

"After a while, I decided I was going to teach him everything I could as long as he was absorbing it."

The first time Yanez walked in a gym, he took to the sport. He loved the workouts, the punching, the atmosphere. "I was astonished," Yanez says of a gym's rhythmic beat.

Rodarte's philosophy is based on conditioning and strength. "He gets stronger and stronger as the fight goes on," Rodarte says. "Other guys get tired and sloppy where Luis is still sharp. The hard work, the yelling, the screaming, the blood, the sweat comes in the gym. You go fight to have a good time."

It hasn't always been a smooth journey. His mother has never seen him box, a topic Yanez, who has four sisters and a brother, isn't comfortable discussing. His parents are divorced.

When Yanez was 14, he started compiling referrals from school administrators for "acting out in class." After he had received 30 referrals, Rodarte gave Yanez an ultimatum: straighten up in school or no more boxing.

"That got my attention. I went home and cried," says Yanez, who expects to graduate from high school this semester. "That was the last of the old me."

A positive force

A two-time Golden Glove winner and two-time U.S. champion, Yanez cruised past his opponents at the U.S. boxing trials in Houston. No one came within 15 points of Yanez, and he won the final 35-11, an impressive result in points-style, four-round bouts.

At the Pan Am Games in Rio de Janeiro in July, Yanez established his international credentials against elite boxers. In the quarterfinals, Yanez defeated Yampier Hernandez, who previously beat him in a Pan Am qualifier.

"I had too much respect for the Cuban because of the Cubans' reputation. I came back to the gym and worked even harder," Yanez says.

Yanez won four bouts en route to the gold, defeating Kevin Betancourt of Venezuela 14-7. Betancourt is ranked eighth in the world.

The successful summer brought more confidence to Yanez, who is a leader and coach at GTO Gym in Dallas' Oak Cliff neighborhood. But GTO is not a gym in the traditional sense. Most of the kids working out aren't training to be elite boxers, they're in it for the exercise.

And it's not just a boxing center. The warehouse-style building houses the non-profit Casa Guanajuato, an educational, cultural and recreational center for the Hispanic community. A mural of the Virgin Mary is on one wall. On the opposite wall near the ring, punching bags and weights, there are pictures of fighters.

The younger kids admire and listen to Yanez as he instructs them. During a 2½-hour workout, he made sure no one slacked on sit-ups and weights.

Yanez's U.S. boxing teammates — most of whom are close to his age — recognized his leadership. They named him one of two captains of the national team heading into the world championships. "When someone falls, I'm there to pick them up," Yanez says. "I like to push people to be their best."

Gary Russell Jr., a teammate who fights at 119 pounds, says Yanez is a natural leader. "He wants to be a positive force in everyone's life," Russell says. "When he sees something wrong, he takes the time to find out what the problem is whether it's in the ring or out."

Yanez possesses a boxer's knack for showmanship, a trait USA Boxing officials would like to see him curb. At the Olympic trials, he mimicked a Superman pose in the final.

"My major concern is that will contribute to judges voting against him," says Campbell, the U.S. coach. "I like that he is confident. I don't want him showing that to the judges. He can show that at the end of the bout when he wins."

Yanez maintains that having fun helps him perform well in the ring.

"Luis accepts challenges," Campbell says. "You've got to present the challenge in the best way possible. I believe that Luis will rise to occasion more often than not."