A montage of Fox Sports properties scrolls past, with the UFC listed alongside the Super Bowl, World Series and other major American events. Then we see an overhead shot of the Honda Center in Anaheim, mimicking the skyline and arena shots that opened the first Ultimate Fighting Championship broadcast exactly 18 years earlier. But instead of generic music and graphics, it’s the familiar Fox theme and feel.

The first UFC on Fox broadcast is a milestone for a young sport. Yet it’s more of a symptom of the sport’s upheaval and progress than the cause. The UFC and mixed martial arts as a whole are still in a state of rapid transition from an underground movement with breakthrough stars to a new world of great potential … and uncertainty.

Technically, little about Saturday night’s broadcast was a “first.” It wasn’t the first UFC appearance on a Fox network — a 2002 bout between Robbie Lawler and Steve Berger was plucked from a hastily assembled fight card to air later on Fox Sports Net’s The Best Damn Sports Show Period. Live UFC fights have been on cable for several years. Mixed martial arts had been on network TV with CBS a few times, with UFC rival EliteXC leading the way in May 2008.

EliteXC’s run, though, was over by the end of 2008. Though the organization had a few good fighters — Lawler once again was on the broadcast, and outstanding female fighter Gina Carano drew plenty of publicity — EliteXC put much of its promotional efforts behind Kimbo Slice, who had risen to celebrity through YouTube videos of his knockouts in backyards and boat yards. It was the equivalent of an upstart basketball league hiring locked-out NBA players but featuring someone who had an impressive reel of playground dunks.

UFC President Dana White had pledged that he wouldn’t do a network TV deal just to say he had one. He waited until he and a broadcast partner could do it right.

Fox studio host Curt Menefee and Dana White sit at a desk perched in an upper level overlooking the Octagon, the distinctive cage in which UFC fighters do their business. Menefee, a polished professional broadcaster, is as comfortable discussing UFC heavyweights as he is introducing NFL studio segments. White, who regularly banters and talks trash with his 1.7 million followers on Twitter, is shouting into the microphone: “First time back on network television, you want to put your best foot forward.” He isn’t containing his nerves and excitement, but did anyone expect otherwise?

The UFC’s road to respectability has been a long one. When lawmakers saw bare-knuckle fighters punching each other (shhhh — no one tell them about indoor lacrosse, which has hockey-style fights with less attentive refs and no slippery ice to take away a puncher’s leverage) and adding in chokes, armlocks and occasional shots to the groin of a future Austin Powers actor and convict, they were not entertained. The organization had to scramble to find venues that would allow such a spectacle, and satellite providers wouldn’t make their airwaves available.

With Los Angeles policeman “Big” John McCarthy helping out from the beginning and stepping into the cage as a referee from UFC 2 onward, the UFC tweaked its rules and evolved from spectacle to sport. White and his partners, Vegas casino moguls Frank and Lorenzo Fertitta, bought the company in 2001 and aggressively pushed to get it sanctioned in every state that has an athletic commission.

The major holdout is New York, where MMA is held back by a combination of political confusion and effective lobbying from an unusual source — union group Unite HERE, which has a long-standing grudge with the Fertittas over their casino employees.

Unite HERE upped the ante by going after UFC advertisers, pressuring them not to associate with fighters and promoters who have been known to let some offensive terms slip from their mouths. So far, that movement hasn’t worked. The Fox broadcast had a lot of the same beer and video game advertisers seen on the UFC’s Spike shows, though the ads didn’t question the viewer’s masculinity as directly as the ads on Spike. The Marine Corps’ partnership with the UFC was once again in full view.

After a break, former UFC heavyweight champion Brock Lesnar joins Menefee and White at the desk. Lesnar is considerably calmer than White even if his message is direct: He wants to avenge his loss to current champion Cain Velasquez and get his belt back.

The UFC’s relationship with professional wrestling has always been uneasy. In Japan, fighters can go back and forth more easily between real fights and wrestling spectacles. In the USA, the fan base overlaps a bit, but MMA and pro wrestling are rivals for pay-per-view dollars. And the legitimized UFC doesn’t need any hints of wrestling shenanigans in its midst.

Lesnar is a giant exception. He’s one of a handful of college wrestling standouts to carve out a career in professional wrestling. After a strong push to make it in professional football, he found an outlet for his athleticism and his competitive drive in MMA. In the UFC, he took a fast track to the heavyweight title.

Chastened by devastating illness, Lesnar no longer brings the brash pro wrestling-style hype to his fights. But other fighters are more than willing to ramp up the smack talk. Tito Ortiz, the “Huntington Beach Bad Boy,” celebrated wins with nasty T-shirts and had a memorable feud with Ken Shamrock, who dabbled in pro wrestling during his long career. The reality show The Ultimate Fighter confines its contestants to a single house in which bragging begets feuds.

The loudest mouth in the UFC these days belongs to Chael Sonnen, another former college wrestler. He has revved up a feud with Anderson Silva, the middleweight champion with moves out of The Matrix, and he surprised nearly everyone who follows the sport by dominating Silva for most of their title fight before the champion caught him with an armbar and forced him to tap out in surrender.

Out of the cage, Sonnen’s feuds are more serious. His budding political career and his real estate career screeched to a halt when he pleaded guilty to money laundering. His fight career was on hold after the Silva fight while he argued with the California commission over his professed need to take testosterone therapy and whether he appropriately told authorities about it. Sonnen continues to argue his points in and against the media, perpetuating a feud a little more real than anything wrestling impresario Vince McMahon can conjure.

Viewers get a trip to Brazil to meet challenger Junior Dos Santos, his family and his old neighborhood. Then we see a story familiar to veteran UFC fans — champion Cain Velasquez and his hard-working immigrant father. Each fighter is humble and grounded with firm family roots.

The new wave of UFC fighters is a polite bunch for the most part. The model is welterweight champion Georges St. Pierre, who speaks with a charming French-Canadian lilt and dresses for press conferences as if he’s doing a cover shoot for GQ. Even those who don’t wear a suit as well as St. Pierre approach their sport and fellow athletes with respect. Heavyweight Pat Barry hugged opponent Mirko “Cro Cop” Filipovic — during their fight.

Fighters often come across a typical boy next door, none moreso than lightweight champion Frankie Edgar, a Jersey kid who is small even for the 155-pound weight class. In prefight interviews, Edgar seems like he’s applying for a job at a hardware store, not preparing to punch and kick someone in a cage. And yet, since wresting the title from long-dominant BJ Penn, Edgar has put on two of the best fights in UFC history against the same opponent — Gray Maynard, yet another college wrestling All-American making his way in the sport. In January, Maynard nearly knocked out Edgar several times in the first round before the champion rebounded to earn a draw. Their October rematch was nearly a replay until Edgar landed a combination in the fourth round to get the knockout and hand Maynard his first loss.

Yet that fight card, according to master number-tracker Dave Meltzer, drew only 225,000 pay-per-view buys, a pale shadow of the seven figures drawn for Lesnar’s title fights and a few other cards featuring the sport’s elite.

The breakthrough stars who built the sport have faded. The retirees include Chuck Liddell, who brought a gun-slinger’s mentality to the cage along with a distinctive Mohawk and facial hair that popped up in various TV appearances and even a Halloween costume on Parks and Recreation. Randy Couture is finally done after fighting past age 45 and delivering the coup de grace to boxer James Toney’s trash talk, easily forcing him to tap out in the first round after the UFC granted a rare pass to an inexperienced MMA fighter just to shut him up. Tito Ortiz and Matt Hughes plug along but are no longer title contenders.

But the UFC has long strived to build its talent pool to be far broader and deeper than boxing’s. As the organization goes global and puts on more and more fights each year, the umbrella keeps growing. The UFC has bought out and absorbed other major promotions, including Japanese rival Pride, which had a roster of fighters that could challenge the UFC’s in its heyday. World Extreme Cagefighting operated separately under the UFC’s auspices for a few years before folding into the promotion and making its lighter-weight fighters available for UFC cards. Soon after Strikeforce took over EliteXC’s deals with CBS and Showtime, the UFC bought it out and continues to operate it separately.

Strikeforce has several marketable fighters, but a couple of them don’t fit into the current UFC setup for one reason — they’re women. While Couture, Quinton “Rampage” Jackson and a few other UFC fighters have taken roles in action films, Gina Carano has gone a few steps farther, winning critical acclaim in a Steven Soderbergh film, Haywire, that also features Antonio Banderas, Michael Douglas, Michael Fassbender, Ewan McGregor and Bill Paxton. While Carano has been out of the cage to start her film career, attention has turned to Olympic judo medalist Ronda Rousey, who has overwhelmed her first few opponents with her submission grappling skills and won over fans with her laid-back charm. And like Carano, Rousey appeals to men for non-fight reasons as well — a typical Web comment: “I wouldn’t last a minute with her either.”

Whether the UFC can make peace with women being in the cage rather than simply walking around it is one of the questions of 2012. White and company have made stars of their “Octagon Girls,” leaving copies of Rachelle Leah’s Playboy appearance on the media’s chairs for a postfight press conference and making sure everyone knew when Arianny Celeste was also gracing the magazine’s pages. Celeste has nearly twice as many Twitter followers as Velasquez.

But even if they’re granted access to the Octagon, Carano and Rousey won’t be the faces of the UFC in 2012 and beyond. No one will. The UFC has no intention of tying its fortunes to one person. Even the loquacious White is less of a media presence than he used to be, making smaller appearances in The Ultimate Fighter reality show and ducking out of press conferences to tend to the business of an expanding empire. The coming years will test the popularity of the brand itself, not a couple of main-event fighters.

After all the formalities, Menefee hands off to the veteran voices of the UFC — Mike Goldberg and Joe Rogan. From there, the broadcast looks more like a typical UFC show. As usual, Goldberg tosses to the invaluable ring announcer Bruce Buffer, who never fails to work the crowd into a frenzy before the referee gives final instructions to the fighters.

Then we get 64 seconds of fighting. Dos Santos and Velasquez trade punches, and Velasquez snaps sharp leg kicks designed to wear down the challenger. But Dos Santos throws a powerful right hand that catches Velasquez behind his ear. His equilibrium disrupted, the champion staggers and falls. Dos Santos quickly lands a couple of punches against his downed opponent. When Velasquez turns on his side, offering no resistance, referee McCarthy stops the fight.

“Big” John McCarthy essentially invented the position of mixed martial arts referee. Most importantly, he pleaded with the original UFC bosses to give him the leeway to bring an end to a fight before someone got seriously hurt. The guiding concept: Is a fighter “intelligently defending” himself? If not, it’s over.

Without that simple concept, which McCarthy correctly applied in rescuing Velasquez from further punishment, MMA never could have been accepted as broadly as it has been. And MMA’s safety record would be far worse. The sport may be too young to conclude that it’s definitively safer than other contact sports, but the rules are designed to get battered fighters out of the fight in a hurry. Boxers spend most of their time head-hunting, rarely winning with good punches to the body, and downed boxers are given eight seconds to “recover” before taking more punishment. Mixed martial arts bouts can end many ways — a stunned fighter may be unable to defend an armbar or a fighter bent over after a kick to the body may fall prey to a choke — and they aren’t given the opportunity to continue if they’re injured too badly to continue immediately. Fights may be bloody, and submissions may sometimes injure arms or legs. But in the hands of experienced referees like McCarthy, serious injuries are rare.

Dos Santos is near tears when his hand is raised and White puts the championship belt around his waist. He tells Rogan in the cage, “I have no words to say what I’m feeling. It’s amazing, my life.” Velasquez also has recovered for a postfight interview. “I will get this belt back, for sure,” he says before giving Rogan a gracious recap of the fight.

When Seth Petruzelli, a last-minute replacement for injured MMA pioneer Ken Shamrock, knocked out Kimbo Slice in 14 seconds, EliteXC and CBS were in deep trouble, having hitched their wagon so firmly to the former backyard brawler. Announcer Gus Johnson roared that viewers had seen “the greatest upset in MMA history.” They hadn’t. Kimbo had an impressive aptitude for the sport and nearly choked out Houston Alexander in a one-sided win in his UFC debut 14 months later, but he was not the Apollo Creed to Petruzelli’s Rocky.

Dos Santos and Velasquez are in another plane, a level of heavyweight fighting Kimbo won’t be able to reach after such a late start in the sport. They’re the vanguard of a new generation of fighters who can’t afford to have a glaring weakness against other multidimensional fighters. A quick tutorial in fighting on the ground won’t cut it — Dos Santos grew up as a jiu-jitsu student in Brazil and still isn’t considered one of the better grapplers in his weight class.

As the athletes grow more sophisticated, the UFC has a challenge of making sure its fans keep pace. A 64-second knockout is an exception. So is the 15-minute slugfest between Forrest Griffin and Stephan Bonnar on the first finale of The Ultimate Fighter that brought the UFC a new audience. Good fighters usually have good defensive skills. Like the NBA, NFL, NHL or MLS, the UFC has to hope fans can stick around when the defense is outperforming the offense. White’s company also has to convince Chuck Liddell fans to become Junior Dos Santos fans or maybe Frankie Edgar fans.

But even as the UFC replaces its pioneers with a new generation, it has plenty of room to grow. With no dominant promotion in the rest of the world, the UFC is aggressively charging into other countries. New-generation fans may also be participants, training in jiu-jitsu and other MMA components in gyms popping up all over. Fox has welcomed the UFC with enthusiasm and will soon turn over many broadcast hours on cable affiliate Fuel to UFC programming.

When Seth Petruzelli knocked out Kimbo Slice in 14 seconds, that was it for EliteXC and the first run of MMA on network television. When Junior Dos Santos knocked out Cain Velasquez in 64 seconds, it was the preamble of a new era. There’s more to come.