The UFC hits Little Caesars Arena in Detroit this weekend, with a UFC 218 pay-per-view event.
Original plans called for a featherweight title fight between Max Holloway and Frankie Edgar, but Edgar was forced to pull out due to injury.
In steps former champ Jose Aldo, who lost the title to Holloway five months ago. The Brazilian great will attempt to make the most of an immediate rematch, which he felt he deserved anyway.
In the co-main event, veteran heavyweight Alistair Overeem and rising contender Francis Ngannou will each look to solidify a title shot.
ESPN's Cheat Sheets are here to break down the storylines -- and predict a few winners -- for UFC 218.
Eddie Alvarez (28-5) vs. Justin Gaethje (18-0), lightweight
Odds: Gaethje -175; Alvarez +155
Ahead of his 35th professional fight, Eddie Alvarez proposed a radical idea to his cornermen. What if they simply watched this one as fans?
"I told [head coach] Mark Henry he should sit next to my wife on Saturday," Alvarez said. "He laughed and shook his head, but I told him I thought he should do it. I think we need to trust our training, trust our instincts and just believe in ourselves in this one."
Alvarez, 33, is one of the most accomplished lightweights of all time -- but at some point in the past two years, he says he stopped trusting himself.
He signed with the UFC in 2014, feeling like he had something to prove. After a convincing loss to Donald Cerrone in his UFC debut, he started focusing more on his opponents and less on instinct, which he now believes has always set him apart.
Clearly it wasn't all bad, as he claimed the UFC championship in 2016. But eventually, Alvarez invested so much effort into winning every second of a fight, he lost the ability to react.
"Since I've been with the UFC, I've tried balancing this idea of being an instinctual fighter and an analytical fighter, and I just went too far the other way," Alvarez said. "My only concern was to win, and I don't know if the by-product of that was a good thing.
"My last two fights, I've been trying to control something that's not controllable. It's causing me to think, which is hurting my performance. I want to be inside this fight. I want to take punches."
It's probably not a bad time for Alvarez to embrace old habits, as Justin Gaethje is a man who will oblige to the type of fight he's looking for.
Gaethje is similar to Alvarez in that he's held a title outside the UFC. The difference is, Gaethje doesn't appear to feel any pressure to prove himself by wins and losses. He brings an action-packed style that instantly netted him 30,000 Instagram followers the night of his UFC debut.
Both lightweights have described Saturday's fight as a competition between the sport's most violent. Whereas Alvarez is returning to that mindset, however, Gaethje has never left it.
"Back in the day, I think Eddie enjoyed that -- but it's pretty taxing on the body as we all know," Gaethje said. "He's become a little wiser in his approach to the fight game.
"Hopefully I won't stick around long enough that it happens to me."
Fight breakdown
Generally speaking, it's not difficult to break down a Gaethje fight. His cards are pretty much on the table going in.
Gaethje wants to brawl. That's it. Sure, we can talk about what he does well technically, but his identity really comes down to a "last man standing" mindset. So far, it's served him well.
Some day, when his chin starts to go, he'll have to drastically change his approach if he wishes to stick around. But for the time being, he's undefeated. He isn't changing anything.
Alvarez is a brawler, too -- but as mentioned above, he's been a reluctant brawler in recent years. He's not inviting wild exchanges, but he's always been good when they find him. Alvarez on autopilot is arguably Alvarez at his best.
This is a Fight of the Night candidate, for sure. And if it turns into that, no one should count Alvarez out. But even if that's what he's mentally prepared for, it might not be what favors him.
A lot of that comes down to durability. Alvarez is four years older and nearing a point where cumulative damage becomes a concern. He's coming off fights in which he was knocked out [by Conor McGregor] and nearly knocked out [by Dustin Poirier].
Fans want action, but Alvarez shouldn't just abandon the ground. Gaethje is extremely active with leg kicks. If Alvarez turns a few of those into takedowns, it should get Gaethje to think twice about throwing them. Turn him into the fence and smother him a bit. Slow things down here and there. Frustrate him.
You're never going to force Gaethje to fight cautious, but at least give him multiple looks. Under fire, he's a bull. His chin is unbelievable and despite the ultra-aggressive approach, he's capable of compact, accurate flurries in a phone booth. It's when an opponent slows the tempo where Gaethje can be most guilty of haymaker headhunting.
If Alvarez wants to be in a fight and get back to his instincts, no problem. But that doesn't necessarily mean he should serve up the exact fight Gaethje wants in doing so.
Prediction: Gaethje via TKO, second round.