(Editor’s note: This story first published at Boxing Junkie, part of the USA TODAY Network.)

Devin Haney and Ryan Garcia have a lot in common but couldn’t be more different.

The fighters, who meet for Haney’s 140-pound title on pay-per-view Saturday in Brooklyn, are both 25 and talented. They’re both from California. They both had strong amateur careers, which included six fights against one another. Each of them won three times.

And they both have become popular professional fighters, with millions of dollars in their bank accounts as evidence of that.

So where are they different? Where do we start?

Haney (31-0, 15 KOs) is a two-division titleholder who has climbed onto pound-for-pound lists after a series of impressive victories over top-tier opponents, including a stunning shutout of Regis Prograis to win his belt in December.

The native of San Francisco has been successful in part because of his mental toughness and discipline, which have allowed him to take full advantage of talent. He could become No. 1 pound-for-pound one day.

Garcia (24-1, 20 KOs) is at least as quick as Haney – probably quicker – and he definitely punches harder than his rival, as his knockout percentage indicates. He also has a few significant victories, most notably knockouts of Luke Campbell and Javier Fortuna.

However, unlike Haney, he failed the only time he faced a pound-for-pound-level opponent. Gervonta Davis stopped him with a body shot in the seventh round.

And, perhaps more significantly, Garcia, who has acknowledged mental health issues, seems to be as emotionally fragile as Haney is stable and tough. Many believe that weakness will be his undoing when they step through the ropes on Saturday night.

The social media star behaves erratically, taking bizarre shots at celebrities or claiming to know who killed rapper Tupac Shakur, to name two examples. He also posted an image of himself smoking what appeared to be marijuana only seven weeks before the fight, which he admitted was a mistake.

A red flag first went up for me the following day, at a news conference in Los Angeles, where he acknowledged that he’s flawed and that it can be difficult for a 25-year-old to handle stardom.

“Sometimes the weight of the world feels like it’s on my shoulders,” he said.

That undoubtedly is true but, at the same time, its a strange comment given that most fighters try to project strength, not weakness in the lead up to a fight.

Haney seemed to be sincere when he asked Garcia repeatedly at the news conference whether Garcia planned to show up for the fight. Garcia never responded, which was strange.

Is Garcia in trouble before he steps into the ring?

Well, Haney is about a 6½-1 favorite (average of multiple outlets), which is a massive spread given Garcia’s pedigree. The oddsmakers obviously believe Haney’s combination of ability and laser focus will be too much for a mentally weak challenger.

Garcia could fool us. Again, he too, has ability and his own natural gifts. And he has overcome obstacles in the past.

For example, he got up from a knockdown to stop the capable Campbell, demonstrating that he can be resilient. And he returned from a difficult 15-month layoff – to deal with his mental challenges – to deliver strong performances against Emmanuel Tagoe and Fortuna.

Stranger things than a peculiar, seemingly distracted contender taking down a champion have happened in boxing.

For his part, Garcia insists that he has improved as a fighter after training with the respects Derrick James. And he suggested that there’s method to his madness.

“You can’t deny all the work that Derrick and I have put in either,” he said Wednesday. “My technique is better, my hands are up, the chin is down. What do you all have to say? The social media is all just noise. I post something and then people think I’m crazy.

“I know what I am doing.”

We’ll see.

This is an enormous challenge for him. Again, Haney has all the ability in the world and is as locked in as anyone in boxing. He’s rolling. We can only guess what Garcia is going to bring into the ring.

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