The UFC will try to help the city of Las Vegas resume some sense of normalcy in the aftermath of last weekend's horrific tragedy with a planned event on Saturday inside T-Mobile Arena.
Here's everything you need to know about UFC 216.
Demetrious Johnson (26-2-1) vs. Ray Borg (11-2)
Flyweight championship Odds: Johnson -1250; Borg +800
Demetrious Johnson says he was pushing his two sons on a swing in his backyard when he received a phone call from the UFC this summer -- threatening to close his division.
At the time, UFC president Dana White was adamant that Johnson accept a title defense against T.J. Dillashaw, a former bantamweight champion who'd never fought in Johnson's 125-pound division.
For a variety of reasons, including the UFC's unwillingness to meet certain financial requests, Johnson refused the fight. He'd already agreed to fight a contender named Ray Borg in an attempt to break the great Anderson Silva's record of consecutive title defenses. He didn't see a need to change opponents.
A standoff between Johnson and the UFC ensued, however, and eventually led to that jarring phone call.
Here was Johnson, literally one win away from breaking one of the most prestigious marks in combat sports history, faced with the elimination of his entire weight class if he didn't take one fight.
His response to the organization? "Close the division."
"I've always been the type of guy, if my wife doesn't want me anymore -- if she downright does not want me -- well then, she doesn't want me," Johnson told ESPN.
"I told the UFC, 'If that's your decision, that's your decision.' I was accepting my fate -- if I was going to have to leave and fight in Japan or move up a weight class, I was willing to do it. I was standing by what I believed in."
Thankfully, the UFC never followed up on the ultimatum, and according to Johnson, the situation is vastly improved. The two sides met in July in Los Angeles (on White's birthday) and settled the dispute.
The historic title fight was supposed to headline UFC 215 last month in Edmonton, but Borg pulled out the week of the fight with an illness. It was quickly rebooked to Saturday's event.
Johnson, 31, says there are still improvements he wants contractually, and he is hopeful those will eventually be addressed -- but as far as this long-awaited, record-breaking title fight, he's content with how things played out.
He drew some criticism for turning down the Dillashaw matchup but received strong support from the MMA community for standing his ground.
For Johnson, it really boiled down to one thing: his job description. The UFC contracts him to defend the 125-pound title against the No. 1 contender, who, he says, is currently Borg. If the promotion wants to change that job title and book a bantamweight superfight or a matchup with a former champion who's never fought at flyweight, he'll be happy to negotiate a price for that.
Until then, he's doing his job. Rather well, by the way.
"People are like, 'You have a short window, look for the biggest fights,'" Johnson said. "But I can prolong that window by fighting people my size. I would say I'm doing well in my career, not taking brain damage. I've been very successful."
Borg made his UFC debut as a 20-year-old in 2014 -- and he's been on the flyweight title radar ever since.
He actually lost his first fight -- a split decision to the hard-nosed Dustin Ortiz -- but his potential was obvious. And even as a young, relatively unproven flyweight, betting lines have tended to favor Borg in the UFC. Well, until now of course.
Borg's quick ascension in the flyweight ranks has been incredible to watch, but that narrative starts to work against him in a fight like this. He has seven fights in the UFC, so he's far from inexperienced -- but he's also just 24, and his performances occasionally reflect that.
He switched camps two fights ago after a frustrating 15-minute loss to a lanky, unorthodox opponent in Justin Scoggins. His standup has come along at Jackson-Wink MMA, but he hasn't shown the level of versatility or power that would threaten the best fighter in the world. His last (and only) knockout came in 2013, against an opponent who had never won a professional fight.
Where Borg is most special is in tight: scrambles, grappling exchanges. He's very good at winning positions and sneaking to the back. He floats well from top position and his ground strikes are significant. He's not one to irritatingly box an opponent's ears on the floor; he's looking to posture and throw dizzying punches and elbows.
That's all well and good, but the problem is that it runs directly into Johnson's best traits. Johnson met Olympic gold-medal wrestler Henry Cejudo in the clinch last year and tore through him like butter. His defensive grappling and offensive strikes in the clinch are second to none. He's never been submitted in his career and adapts as fights go on -- making his opponent's (typically) small path to victory even tighter.
In fact, that's probably why so many fans think Johnson is boring. His fights are essentially over by the third round, as he's exploited opponents' holes to the point of rendering them harmless.
Borg is one of the most talented 24-year-old fighters in the world, if not the most talented. And at that age, he's always adding new tricks. But he still has holes and he doesn't have three, four, five game plans to fall back on if Plan A isn't cutting it. Johnson will feast on that.
Prediction: Johnson via submission, third round.