It's hard to measure what success looks like against Jon Jones. The man has been fighting professionally since 2008, and no one has legitimately beaten him.

If we're being honest, though, the most recent attempts to halt Jones' perfection -- failed title bids by Alexander Gustafsson (December) and Anthony Smith (March) -- were downright disappointing.

Gustafsson (18-5) took Jones to the brink of defeat in a 2013 title fight, but in their highly anticipated rematch at UFC 232, he managed to land only 22 strikes. And Smith (31-14), who is known as one of the scrappiest, most unbreakable athletes in the UFC, inexplicably froze against Jones. He survived five rounds but never truly went for broke. He has admitted as much since.

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Such is the buildup to Saturday's UFC Fight Night in Stockholm. Gustafsson and Smith will square off in the main event, each fresh off a lackluster showing against the dominant champion.

Neither is likely to earn a title shot in the near future, which raises the obvious question: What are they really fighting for?

Listen to their responses, and you'll know. This fight is not about sorting out rankings or title opportunities. In a way, Saturday's bout is taking place for no one other than the two men involved.

Gustafsson needs to establish who he is, now that he's no longer the man who "might be Jon Jones' kryptonite." And Smith needs to make amends in his own head, for his frustrating performance in a bout he'd waited years to reach. When you look at it that way, there's actually quite a bit at stake.

ESPN Stats & Information

By the numbers

Minus-89: Significant strike differential for Smith in his last fight, against Jones, according to UFC Stats. It was a career worst -- as was the minus-37 differential for Gustafsson in his most recent fight, also against Jones.

9: Knockdowns for Gustafsson in his UFC career, which puts him fourth in light heavyweight history behind Chuck Liddell (14), Mauricio "Shogun" Rua (14) and Lyoto Machida (11).

3: Finishes for Smith in his four fights since moving up to light heavyweight last year. That ties him with Thiago Santos and Johnny Walker for most UFC light heavyweight finishes since the start of 2018.

84.8: Percentage of takedowns successfully fended off by Gustafsson in his UFC career, the fifth-best number all time among 205-pounders.

6: Consecutive victories for Smith in which he finished his opponent.

Source: ESPN Stats & Information

A look back

No one else has made Jon Jones look like a beaten man, as Alexander Gustafsson did in 2013. Jones won the decision that night, and Gustafsson won fans. Josh Hedges/Zuffa LLC/Getty Images

Five vs. five

Fighting words

"It's not really about Gus, you know? It's not even really about winning or losing. It's not about getting back to the title. I'm not sitting here saying I don't want to win; that's not what I'm saying. I'm saying I haven't even considered the fight in a win-versus-loss situation, 'cause honestly I don't give a s--- what happens. I just want to perform. I want to go in there, I need to destroy something to get this feeling out of my stomach, this burning, sick feeling that I can't shake. The only way I'm going to do that is I gotta let it out on somebody. I wasn't able to let that out on Jon, and I didn't. So I still have it." --Smith, talking to ESPN about how the lingering disappointment of his loss to Jones shapes his mindset for the Gustafsson fight

Dom and Gil's film study

The keys to victory for Gustafsson (according to Dominick Cruz and Gilbert Melendez):

The keys to victory for Smith (according to Cruz and Melendez):

And the winner is ...

On paper, this is Gustafsson's fight to lose. He's the more technical striker and probably the better athlete. Smith has finishing prowess, which makes him a dangerous underdog, but Gustafsson's chin is still above average and his defensive wrestling is underrated. It's also a very quick turnaround for Smith. Brett Okamoto's pick: Gustafsson gets it done, third-round TKO.

What to watch for (beyond the main event)

Top-heavy with light heavies

The light heavyweight fisticuffs get going before the main eventers hit the Octagon, as the fight leading up to Gustafsson vs. Smith is also a 205-pound bout. One of the two fighters in the co-main event has something to overcome, while the other would love for the status quo to keep rolling forward.

Jimi Manuwa will be trying to halt a three-fight skid when he faces Aleksandar Rakic, an Austrian who is 11-1 and has not lost since his MMA debut in 2011. He is 3-0 in the UFC.

There was to be a third 205-pound fight at the top of the card, but Volkan Oezdemir vs. Ilir Latifi was canceled on Thursday after Latifi, who fights out of Stockholm, was pulled because of a back injury.

Fighter, cop, actor ... and matchmaker

Nick Hein, on the set of "Diese Kaminskis," prepares to film a fight scene. Dennis Grombkowski/Zuffa LLC/Getty Images

Four things you might not know about German lightweight Nick Hein, who faces Frank Camacho in a preliminary bout: