LAS VEGAS -- EAGLES CIRCLED THE Octagon, from nearly 400 feet above. One fight occurred under the backdrop of an ancient temple, another in a colorful Mexican plaza. When Sean O'Malley and Merab Dvalishvili walked out for the main event, they did so under a Mexican city skyline set in the future.

Each "world" represented one of six chapters in a "love letter to Mexico," inside Sphere's 160,000-square-foot interior at UFC 306.

Dubbed Noche UFC, Saturday night was meant to be one of the most unique and ambitious sporting events ever produced. For many of the 16,024 in attendance, it was. Actor Brandon Sklenar, an avid fight fan who has attended multiple UFC events in the past, described the experience of the ever-changing worlds as a real-life Mortal Kombat, the video game franchise known for its realms.

For UFC CEO Dana White, this past weekend was an homage to Mexico as it celebrates its independence ahead of the official date, Sept. 16. According to White, the UFC spent $20 million on the event and employed a staff of more than 500 people to pull it off.

The vision, which started one year ago when White attended a U2 concert at Sphere with Tom Brady, aimed to combine a traditional night of sports with the megawatt entertainment capabilities of the $2.3 billion venue. The one-of-a-kind building opened last September, making it difficult to even compare Noche UFC to anything the sports world has ever seen.

"I don't know if [anyone has] ever seen anything like this," White said Saturday after the event. "If you have, I don't know where the f--- you live or where you came from."

The fights themselves were hit and miss, with White even joking he hoped viewers tuned out before the final two championship fights, both of which went the distance. But the experience of the event did a lot to make up for any lulls inside the Octagon.

"What UFC was able to do so beautifully was enhance the action in the Octagon without distracting from the main events," Joel Fisher, executive vice president of Marquee Events and Operations at Madison Square Garden Entertainment, told ESPN.

All night, a collective sea of phones mirrored the interior screens of Sphere as the audience filmed the spectacle.

During the prelims, Mexican bantamweight Irene Aldana suffered arguably the worst cut in MMA history on her forehead. Once displayed on Sphere's screen, that cut turned into a 50-foot horror scene for the fans in attendance. The atmosphere of Sphere changed from fight to fight, taking the audience through a constantly evolving experience. The UFC even hid Easter eggs in the films shown during the main card, with White promising $25,000 to anyone who could find all six. (As of Sunday, no winner had been announced yet.)

White said he is looking forward to reviewing the public's reaction to the event in the coming days, and praised his team for its "seamless" execution of what he envisioned. No matter the reaction, the UFC delivered this event exactly the way it hoped. Now, the question turns to whether it will do it again -- whether this could become more than a "once-in-a-lifetime event," as White has described it -- and perhaps most importantly, whether other sports leagues might try to replicate it.

"It'll take the NBA or one of these companies with a ton of money [to do it]," White said. "But we showed everybody tonight what's possible. You can do more than concerts here. So, who's next?"

WHEN WHITE FIRST revealed his vision to UFC chief content officer Craig Borsari, Borsari estimated the company could pull it off on a budget of $8 million. Normally the budget for a UFC pay-per-view event is between $2 and $2.5 million, White told Bloomberg.

There are a lot of reasons the budget more than doubled. The issue of lighting the Octagon in such a cavernous venue proved to be the greatest challenge. The UFC explored a host of potential solutions, before finally partnering with an engineering group to design a lighting system installed behind Sphere's screens. Even though MSGE designed the Sphere to be capable of hosting live sports, the specific lighting requirements of the UFC Octagon were tricky.

"The reason there are even gaps to begin with between those LED nodes is that all of the building's sound comes from behind that," Borsari told ESPN. "The LED we normally come across has a backing to it, so our solution wouldn't have worked. We got lucky."

As the event came together, Borsari focused on ways to take what was happening in Sphere to the viewer at home, which resulted in the additional cost of a second production truck. The cost of the films the UFC created was higher than expected, both in terms of whom the company collaborated with (numerous Emmy-winning directors, costume designers and filmmakers) and in formatting them for the world's largest spherical entertainment venue.

"Just the resolution you need to get these videos to work on this media plane -- the render farms," Borsari said. "I didn't anticipate rendering content for days just to get something to look right. That is not cheap."

The cost of the event was ultimately more than offset by its financial success. According to White, Noche UFC produced a record-breaking $22 million gate and also broke the company record for merchandise sold. In May, Turki Alalshikh, the chairman of Saudi Arabia's General Entertainment Authority, announced a "strategic agreement" with Riyadh Season and the UFC. As part of that deal, Riyadh Season -- an annual state-managed sports and entertainment festival -- sponsored the event for an undisclosed amount of money.

And the real profit of this event might still be yet to come. Borsari strongly believes other sports leagues will attempt to do something similar to Noche UFC, because of the benefit of added fans.

"I think this can be a game changer for your brand and your sport," Borsari said. "I feel like we did a good job introducing our sport to probably some newbies who had never watched MMA before. Reimaging what you've been doing is a way to open opportunities for growth. Every sport wants to grow, and they're all looking for ways to expand. This is an obvious one."

COULD SPHERE BE the future of sports? Could one day, a consumer buy a live event ticket, not only for the matchup on the field or court or canvas, but for the "world" in which the event will take place?

White and the UFC aren't ready to commit to a return to Sphere.

"No. I'm under contract with MGM," White told the media Saturday. "This thing, I told you guys leading up to this, the way that this whole thing played out, tonight was meant to happen. It happened. We did it. We killed it." The UFC signed a seven-year agreement with T-Mobile Arena (co-owned by MGM Resorts International) in 2017 to host at least four events yearly at the venue. After running a Fight Night card at T-Mobile Arena on Mexican Independence Day weekend in 2023, boxing promoter Al Haymon secured the venue for Canelo Alvarez -- one year out.

"Canelo's one of those guys that I respect and hey, good on Haymon," White told ESPN's Mike Coppinger in July. "Haymon snatched that date right away from me."

With the UFC's Sphere future on hold for now, one sport with a growing presence in Las Vegas is professional basketball. The city is home to the semifinals and finals of the NBA Cup, along with NBA summer league and the WNBA's Las Vegas Aces.

Denver Nuggets point guard Jamal Murray attended Noche UFC and said he could easily envision the NBA going in on the concept. In some ways, he said the league already did in 2020, when the conclusion of the 2019-20 season took place in a bubble environment in front of virtual fans at Walt Disney World Resort because of the COVID-19 pandemic. Standing on the floor of Sphere during the UFC prelims, Murray said he would "love" to play a basketball game in that kind of environment, and went so far as to say it would be easy for the league to do.

"You could play on different planets, underwater," Murray told ESPN. "You can really get as creative as you want, which means there's no limit to it."

If other leagues want that same benefit, it won't be as simple as copying what the UFC did. But as White said, the event showed what's possible.

"Because Sphere and its technological capabilities are unlike anything, anywhere else in the world, other sports won't simply be able to replicate what we did with UFC," Fisher said. "But I do think it will make them think hard about what they are delivering to fans and how to engage them in new ways. And if they want to do that with us at Sphere, we are open to those conversations."

ESPN's Stephen A. Smith said he has very little doubt the concept will spill into other leagues, because the history of sports features leagues, owners or teams either copying or trying to one-up others. Despite White's opinion that boxing would "never" invest in an event like Saturday because promoters would balk at the cost, Smith said he believes boxing will likely be the first sport to follow suit, and other leagues won't be far behind.

"Everyone is always looking to replicate," Smith said. "Jerry Jones did Jerry World [AT&T Stadium] in 2005, and there have been six more billion-dollar venues built in that time. What you'll see now is other sports leagues taking a look at this and asking themselves, 'How can we do this, but even bigger?'"

Before Noche UFC, White told The Associated Press he believed the event would go so far as to impact how arenas are designed. As technology constantly improves and the demand for that technology infiltrates sports, arenas will have to adapt. The definition of "entertainment" at a sports event will evolve.

"You've got mascots bouncing off trampolines and dunking basketballs, jugglers -- I've been to a lot of NBA games and they've got some weird s--- going on at halftime," White said. "Imagine if you started building these arenas where you could actually do some entertaining stuff. This was my vision for this fight. The people who build these arenas, the whole arena game is going to another level. I actually had a meeting here tonight about an arena we'll probably be a part of here in Las Vegas. So, the whole game is changing. It's incredible."