Ding! A thundering, rage-filled anthem pounds over the loudspeaker as Noah Weisman marches toward the steel cage to meet his opponent. Spotlights swirl; people cheer. Weisman shadowboxes in time with the music. His eyes are fixed ahead of him in a steely glare. No distractions tonight. This is the biggest fight of the 31-year-old’s life.

At the ring’s edge, the cut man smears Vaseline over Weisman’s face so the punches will slide right off. An official looks over the Burlington fighter and sends him into the cage, which is menacingly referred to as “the steel.” Not all mixed martial arts (MMA) bouts are fought inside a cage. But for this event — titled “King of the Cage: No Mercy” at the MGM Grand at Foxwoods Resort Casino in Mashantucket, Conn. — the steel is an essential prop. Many fighters leave the ring with angry red welts on their backs courtesy of the unforgiving steel.

Inside the cage awaits Weisman’s opponent, Sean Wilmot. The husky, bald fighter from Worcester, Mass., has a 6-4 record. Weisman zeroes in on him like a fighter pilot locking his target in the crosshairs. His stare-down lasts until the fight bell sounds.

Intense as his gaze may be, the 5-foot-11, 156-pound Weisman looks less like a dangerous fighter than does his beefy opponent. Weisman is lean and sinewy, his head topped with short, wavy curls. A pencil-thin beard frames his jawline. On his right shoulder, a lone tattoo in loopy script reads “Fetish” — the name of the short-lived company he started with friends years ago.

The bell dings, signaling the start of the first round. Weisman springs from the red corner. He throws one kick, two kicks. Wilmot connects on some punches before backpedaling. In a blink, the Massachusetts fighter is against the steel. Weisman seizes the opportunity. A few swift knees to the abdomen, and Wilmot falls to the mat.

This suits Weisman, a rangy grappler who is quick to exploit an opponent’s weakness on the ground. Years of Brazilian jiu-jitsu taught him how. On the mat, Weisman works to contain Wilmot. A couple of knees to the mouth and his rival becomes more subdued.

“Don’t let him breathe!” a fan shouts as Weisman slides around to dominate Wilmot from another angle.

The rest of the five-minute round is spent wrestling on the mat. Both men are tired. But the bell can’t come soon enough for Wilmot, who has been dragooned by the “Hebrew Hammer” for most of the round.

Ding, ding, ding!

Mixed martial arts is often referred to as the fastest-growing sport in the world. It combines wrestling, boxing and a variety of martial-arts traditions, including judo and tae kwon do. In a nonchampionship bout like the one at the MGM Grand, fighters compete for three rounds of five minutes each. Championship matches are longer — typically five five-minute rounds. As in boxing, fighters can win a bout in several ways: by knockout, submission, technical knockout or decision.

While fans may want to see a stunning knockout, most fights are determined by the referees, who look at the number of strikes, submissions and takedowns each fighter has accumulated. Unlike in studio wrestling, MMA fighters may not gouge eyes, butt heads, pull hair, kick groins or bite.

For Weisman, this fight means the difference between being average and being great. A win could spell the end of his career selling used cars, just scraping by. A win could prove that he’s made something of his life, that his troublemaking days are behind him. It could mark the beginning of a new life for him and his two young sons, of whom he has sole custody.

A notch in the W column of his fight record would also bring Weisman one step closer to achieving his dream: to fight for one of the major MMA sanctioning organizations. Like boxing, the sport has a number of these. The biggest is the Ultimate Fighting Championship (UFC), which controls more than 90 percent of the MMA industry. Strikeforce, World Extreme Cagefighting (WEC) and DREAM, a Japanese league, make up the rest of the pie. Weisman would be happy landing in any big show.

As for the possibility of losing this fight, Weisman doesn’t even want to contemplate it. He hasn’t worked this hard — training three or more hours a day, six days a week — to be vanquished on national television as potential sponsors, agents and representatives of larger MMA organizations with contracts to offer look on. He didn’t work his way out of a restless, troubled youth to lose on this night in Connecticut.

Weisman’s rise as a professional MMA fighter is the classic underdog tale. During his adolescence and early twenties, officers of the Burlington Police Department knew Weisman’s name well. He landed in court for two misdemeanor charges and a handful of lesser offenses. The young man, once an A student, even served a few days in prison.

Weisman was born on August 25, 1979, to a black father and a white Jewish mother. The nurses in the hospital called him Bruiser because of his above-average birth weight — 10 pounds, 1 ounce — recalls his mother, Gigi Weisman. He had a globe of black hair, she says, which prompted nurses to send him home with a brush.

When Weisman was 3, his father, Newell Roberts Jr., left the family, which included the couple’s daughter, Lisa. Three years later, Gigi married Jerry Weisman, who had two children of his own. Jerry Weisman adopted Gigi’s two children, and she adopted his two.

“We were like the Brady Bunch,” says Hannah Weisman, Noah’s stepsister. “But we don’t differentiate between step- and birth siblings.”

Jerry and Gigi had another child, Jacob, bringing the total to seven people living in the family’s New North End home. All the kids were brought up Jewish, though some were more devout than others. The fact that Weisman’s King of the Cage debut falls on Kol Nidre, the eve of the holiest day of the Jewish calendar, makes his mother shake her head and laugh. “It shouldn’t surprise me that he’s fighting on Yom Kippur,” she says. “He and his sister once snuck out of temple to get a slice of pizza during the high holidays.”

Gigi Weisman remembers her son as a sensitive boy who took it hard when classmates teased him, even in silly ways like rhyming his name with nonsense words. Once, his mother recalls, Weisman fretted over his eyelashes. He thought they were too long.

“I told him, ‘Don’t worry. Your eyes will grow into them,’” says Gigi Weisman, who is well known around town for her work as a children’s musician.

The sprawling family made it easy for Noah, the middle child, to get lost, his sister Hannah says. Outside the home, Weisman regularly endured intolerance on two fronts — he was black and Jewish. On more than one occasion, Weisman recalls, he heard the word “nigger” flung in his direction as he walked to school. Once a teacher told him there was no such thing as a black Jew — even though Weisman celebrated all the Jewish holidays with his family, went to Hebrew school and was preparing for his bar mitzvah.

The Burlington in which Weisman grew up was a much whiter place than it is now, says Brian Williams, Weisman’s former English teacher at Burlington High School. Williams is now the principal of the Integrated Arts Academy at H.O. Wheeler School.

Weisman did enough work to maintain good grades but wasn’t that invested in school, he says. Former teachers remember him as cerebral and mature in his worldview — but that didn’t prevent him from getting into trouble.

“When the tune being played wasn’t the tune he wanted to hear, he tried to make his own tune,” Williams says. “The one-size-fits-all curriculum wasn’t for him.”

Despite his obvious athleticism, Weisman could never find a sport that worked for him at school, either. He was one of physical education teacher Pavel Dvorak’s better students, but he wasn’t a standout. He just couldn’t find a way to connect.

The single event that would come to define Weisman’s high school and early adult years happened just after his bar mitzvah, the Jewish rite of passage for adolescents. For years, Gigi Weisman told her oldest son he could meet his birth father, whom he hadn’t seen since he was 3, after this milestone. As it approached, she recalls, she sensed that Weisman was teetering on the brink of revolt. She warned his birth father, who by then had a new life and family in Rhode Island, that their son was volatile.

“‘This is a kid who could go either way, so stay connected,’ I told him,” Gigi Weisman says. “When you’re 15 and someone leaves you, that’s really bad. It tipped the scales.”

The meeting between restive son and absent father happened when Weisman was 15, at the University Mall over Chinese food. It didn’t go well.

“That was a trigger point,” Weisman says. “I was a straight-A student up to that point. I met him, and then we didn’t see each other for years after that.”

Weisman is quick to point out that he has smoothed things over with Roberts in recent years. The two are in occasional contact, and Roberts even came to his son’s last pro fight. Weisman didn’t want to hold a grudge, he says.

But that ill-fated reunion was everything Gigi Weisman had feared. “I think it was extremely damaging,” she says.

After the meeting, Weisman, who had been straddling the line between order and rebellion, stepped onto the wrong side. At 15, he moved out of the family home and into the home of a friend. Eventually, he got his own apartment and worked as a dishwasher to pay the bills. Many friends cycled in and out of the apartment, staying a few months at a time and helping with the rent. They called the place the “homeboy hotel.”

Weisman still attended school, but it wasn’t a priority. He just wanted to finish.

“Looking back, it was definitely not the right choice to make,” Weisman says of his exodus from home. “But it’s a character builder, shall we say.”

In 1997, while bouncing from one restaurant job to another, Weisman was arrested for simple assault and received a suspended sentence. After violating the conditions of his release later that year, he ended up spending three days in jail. Weisman is coy about his past indiscretions and especially reluctant to talk about that rocky period. The past is the past, he says.

When a car salesman friend encouraged Weisman to try his hand at the auto business, the young man couldn’t resist. He turned out to be a natural salesman, with equal amounts of charm and earnestness. For the past seven years, Weisman has hawked cars at a number of local dealerships, most recently Burlington Mitsubishi.

As he got serious about his fighting training, however, Weisman had to give up working full time. He wholesales cars here and there, but most of his time is devoted to priming his body and mind for the next fight.

And much of the rest Weisman gives to his two sons, 9-year-old Zachariah and 7-year-old Ezra. He loves to do “family things” with the kids and his longtime girlfriend, Cilla Rybicki, such as hiking, swimming and apple picking. At home, Rybicki guides the kids in yoga sessions. Weisman works out with them in his makeshift basement gym, teaching them to punch and kick on their own kid-sized punching bags.

Every morning, Weisman walks his sons to Flynn Elementary and hangs out with them on the playground until the bell rings. He’s trying to be there for his boys in a way his father wasn’t for him, he says — to break the cycle. The boys are his motivation for fighting.

Assuming his career continues to advance, the payday for Weisman and his family could be substantial. Top fighters in the MMA big leagues can get five to six figures for a fight, says Tom Murphy, Weisman’s coach and a former UFC heavyweight fighter. While it’s laughably less than boxing’s multimillion-dollar payouts, the MMA purse is growing. Sponsorship deals are even more lucrative.

But the ifs are numerous and looming — if Weisman gets offered a contract, if he makes connections with sponsors, if he puts on an entertaining show, if he stays healthy.

Professional MMA abounds in these variables, which is why the automobile business still appeals to Weisman — it offers job security. If he ever sustains a career-ending injury, he figures, he can go back to selling cars.

Round Two

Ding! Weisman trots to the center of the ring, his body sleek with sweat. He plays with his opponent, Sean Wilmot, throwing a few warning punches as he gets his legs moving. His gaze is fixed on Wilmot’s stocky frame. There is no sign of fatigue.

Off in the corner of the theater, about 50 feet from the cage, Rybicki watches the fight. Her arms are crossed over her chest; her face is set in a wince. She shifts her weight from foot to foot. She hardly slept the night before. Watching Weisman fight is hell for her, she says.

With a knee to the abdomen, Weisman has Wilmot down in the center of the mat. Wilmot reacts instinctively, throwing his feet in the air to block Weisman. The defensive move looks like an airplane lift one might do with a child.

Weisman deflects Wilmot’s blocks and reaches over the top of his knees, landing three punches to the head right in a row. Pow! Pow! Pow!

“Bust him, Noah!” one of his fans cries out.

Weisman is dominating, and he knows it. Even though his left shoulder sags from a separation sustained during a recent training spar, Weisman is full of fire.

Ding, ding, ding!

Weisman’s life changed when he found Brazilian jiu-jitsu in 2002. He first went to the classes on the suggestion of his best friend since kindergarten, Sean McDonough, who had been taking them for years. The martial art gave Weisman structure and a channel for his native athleticism and energy.

“He became a real student for what I feel is the first time in his life,” his mother says.

Brazilian jiu-jitsu, like most martial arts, has its underpinnings in respect and discipline. During classes at Vermont Brazilian Jiu-Jitsu & Self Defense Academy in Williston, Weisman learned his moves alongside the same police officers with whom he’d had run-ins years before. In BJJ, they could all be equals.

The classes also gave Weisman a new way to take pride in his heritage. He’s well aware of the tradition of Jewish fighters who have excelled in combat sports, primarily boxing. In the interwar period in the United States, boxers with last names such as Rosenbloom, Goldstein and Levine dominated the sport. Between 1910 and 1940, nearly a third of the boxers were Jewish. Twenty-six became world champions.

In 2005, Weisman met Tom Murphy and began training with him at the Fitness Zone, the gym Murphy owns in St. Albans. Thanks to Murphy’s credentials as a pro fighter, the Fitness Zone has become the preeminent MMA training facility in the state.

Murphy is a tower of a man with rippling biceps, pectorals the size of serving platters and the telltale swollen ears of someone who has wrestled for decades. In 2005, he appeared on a Spike TV reality show called “The Ultimate Fighter.” He’s enjoyed some success in the UFC and is currently a contract fighter for the Mixed Fight League in Montréal.

Weisman was drawn to MMA for the challenge. Plus, he was tired of playing the armchair quarterback, critiquing bouts without participating himself. “You look at some of these guys doing this on TV and see the mistakes they’re making and say, ‘I can do a better job,’” he says.

In 2007, Weisman fought his first MMA bout. It lasted just 52 seconds and ended when Weisman issued a blistering knee to his opponent’s stomach. The other fighter withered, and Weisman was named the winner.

That win led to an eventual headline bout at the first Burlington Brawl — the region’s premier amateur MMA series. All Weisman’s friends, many of whom he has known since kindergarten, came out to support him.

Weisman’s mother and sister both remark on his ability to nurture and maintain lifelong friendships. But at that bout, seeing familiar faces in the crowd wasn’t necessarily a boon. “Having grown up here and having everyone I know here adds to the pressure,” Weisman says. “I didn’t want to get my butt kicked.”

He didn’t. Weisman won handily in that match against Tim Stoll, beating him with a technical knockout in the first round.

The electricity of the crowd and the elation of winning stuck with Weisman. Eager to make the tingling sensation of victory last, he couldn’t wait to get back in the ring. He wanted to feel like he was doing something important, he says — fulfilling his destiny.

It didn’t take long for Weisman to enter the pro ranks, buttressed by Murphy’s coaching and encouragement. “Noah is extremely gifted genetically. He has very good combinations; his recovery is good; he’s got fast muscle fiber,” Murphy says. “He’s the type of person who should be a professional athlete.”

Murphy sees a bright future for Weisman in the professional MMA ranks. But he advises his student to have patience. Weisman’s biggest fight will come in two or three years, Murphy says. He qualifies this statement with another big if: if Weisman can continue to learn and keep his life on a straight path.

To prepare for the event at Foxwoods — one of the four bouts Weisman will fight this calendar year — Weisman spent countless nights at Murphy’s gym. An average training session goes like this: a five-minute warm-up on the jump rope; five rounds of five different plyometric drills, including 25 bear crawls, 75 push-ups and 125 air squats; plus cage drills, shooting takedowns and partner grappling. Murphy shouts gruff words of encouragement. By the end of the session, Weisman is soaked in sweat.

With this intense training schedule, Weisman requires a dedicated support system to meet his children’s needs when he’s gone. His mother and Rybicki pick up the slack, taking care of the boys in their father’s absence.

“I’d do anything to help him,” Gigi Weisman says.

Her son hopes to return the favor. He says he dreams of paying off her mortgage and setting her up for retirement.

Round Three

Ding! Weisman charges toward Wilmot, grabs him around the neck and pulls his head down. A swift knee to the throat and Wilmot buckles.

Down on the mat, Weisman swings to Wilmot’s side and tries to gain position. From a half-squatting stance, he throws punch after punch, though none is powerful enough to break Wilmot.

In 10 minutes of fighting, Weisman has connected on more punches and kicks than has his opponent. He feels the win. He just has to battle for a few minutes more.

Weisman backs off Wilmot to get a better angle. Despite having been abused for the past two rounds, Wilmot springs up with surprising speed. He’s found his second wind.

Wilmot shoots toward Weisman and slides onto his knees to take his opponent out at the waist. But he can’t drop him.

Weisman bullies Wilmot against the cage, where the pair, heaving and exhausted, get in a few final blows. The 10-second alarm sounds. Wilmot lets sail two powerful uppercuts. Weisman throws one last jab.

Ding, ding, ding!

It’s over. Three rounds and 15 minutes of combat come down to the judges’ decision. Weisman’s fans — all 50 of them, who came here from Burlington and beyond — are on their feet.

The announcer calls the two men to the center of the ring.

“The winner by unanimous decision, representing Rail City MMA, is NOOO-AHHH WEISSS-MANNN.”

Weisman flashes a little thumbs-up to his friends before throwing his fists above his head. Cameras flash. Another battle fought and won. He can’t wait for the next fight.