Brandon Rios appears as if he has a devilish grin permanently attached to his face. Outside of the boxing ring, Rios loves to joke and prank and rarely takes much in life seriously.
There has been a noticeable change in Rios' demeanor in recent days, however.
He has convinced himself that nobody is giving him a chance to defeat Manny Pacquiao when they meet in the headliner of an HBO Pay-Per-View bout at CotaiArena in Macau, China, on Saturday, and is none too happy about it.
Rios' wrath is directed toward fans, media, Pacquiao trainer Freddie Roach, his promoter, Top Rank, and pretty much everyone not wearing his team's colors.
"They're treating me like I'm some sort of joke and that I'm just showing up to be the victim for Manny Pacquiao," Rios said. "I'm nobody's tune-up fight and they're going to find that out soon enough."
Pacquiao is one of the biggest names in boxing and, despite back-to-back losses, remains one of its best fighters.
Rios is an action fighter who loves to trade, the wilder the better, but he's perceived by many experts as too slow and too easy to hit to beat Pacquiao.
Roach has made no secret of his confidence.
"The more I see of Rios in the tapes, the better I feel," Roach said. "He's just a tough guy and tough guys don't win fights. Manny can outbox him and he can do it with ease."
That's the kind of thing that has regularly gotten Rios' blood boiling over the last few weeks, as fight night nears and he has heard more and more people dismissing his chances.
It's not helping that Pacquiao is one of the most beloved boxing figures in the world with a large, devoted fan base.
More than 30 years ago, the great Roberto Duran found himself in much the same situation as Rios. Duran was the tough guy who was moving up in weight to face Sugar Ray Leonard, the darling of the media and of the fan base.
Duran was steamed by all the love shown to Leonard, who by the time they fought in Montreal on June 20, 1980, was already starring in television commercials and was one of the biggest names in all of sports.
It irritated Duran to no end, but he didn't let the star treatment given to Leonard negatively impact his performance.
In a physical, grueling fight waged mainly in the trenches, Duran won a unanimous decision.
He said Rios can do the same thing, but shouldn't be thinking of Pacquiao as a star but simply as another boxer.
"First of all, the stars live in the sky," Duran said. "On Earth, everyone is an equal. … I'd just give some advice to Brandon Rios: Go in and attack and don't be afraid and don't hesitate, because he can win if he fights intelligently."
Rios has never been afraid to attack – his fights with Mike Alvarado in 2012 and 2013 were among the best in each year, and featured Rios relentlessly charging Alvarado – but he doesn't get a lot of credit for his boxing skills.
Rios won 230 of 265 fights as an amateur and was an alternate as a featherweight for the 2004 U.S. Olympic team.
That's another thing that irritates Rios – that his amateur career is largely being overlooked. Just because he loves to fight, he said, doesn't mean he doesn't know how to box.
Rios' father, Manuel, trained him as an amateur and was exceptionally hard on his son.
"He didn't play games," Rios said of his father. "He was really tough on me. He didn't [expletive] around. He would cuss at me when he wasn't happy with what I was doing and say, 'Don't waste my time. Do you really want to be a fighter?' He'd kick me out of the gym for a couple of days."
That's where Rios got his relentlessness from, but relentlessness doesn't win a lot of amateur bouts. Particularly under the scoring system used at the time Rios was an amateur, boxing skill was highly rewarded.
"However I want to fight, I can fight," Rios said. "I'm being short-changed all the time. Nobody is giving me credit. Freddie Roach, he apparently thinks I'm some kind of [expletive] pushover. Well, believe me, I'm going to prove to Freddie Roach and everyone else that I'm no pushover. If they picked me because they thought I was easy, they made a bad mistake."
Pacquiao was knocked out cold by Marquez in his last outing, and Leonard said it will be hard for the Filipino congressman to forget about it, no matter how hard he tries.
Leonard suggested that Rios do as Duran suggested and fight, not box, Pacquiao. That, he said, will remind Pacquiao of the danger he's in and of the last result.
"What Brandon Rios needs to do is not let Pacquiao forget about what took place in his last fight," Leonard said. "Rios has to jump right on top of Pacquiao, because what happens is when you get knocked out in the fashion that Pacquiao was knocked out, it becomes like an Achilles' heel."
If Rios can duplicate Marquez's feat and knock Pacquiao out, that familiar smile will surely crease his face once again.