Joseph ‘Jojo’ Diaz Jr. is viewed as the toughest test to date for Devin Haney, in terms of both accomplishment and physical strength.

The general breakdown of the forthcoming WBC lightweight title fight is that Las Vegas’ Haney is best served to box his way to victory, while Diaz’s best—if not only—chance of winning is to make things as rough as possible for the defending titlist.

Diaz doesn’t disagree with that assessment, although stopping well short of endorsing the generalization.

“When I say outdog, it’s more than just going in there, being a tough fighter and bang it out,” Diaz vowed while discussing the title fight scheduled for December 4 at MGM Grand Garden Arena in Las Vegas. “I’m not just gonna throw punches just to throw punches.”

Haney (26-0, 15KOs) wasn’t quite buying the claim, though daring his upcoming foe to put those words into action. That led to the next promise being made directly to his upcoming foe at a recent media event.

“Bro I’m gonna break your ass down,” Diaz vowed. “I’m gonna break your ass down. I’m gonna eat your ass alive, just be ready.”

A contentious buildup preceded the two sides eventually finalizing a deal earlier this month. Las Vegas’ Haney agreed to terms well in advance, waiting on Diaz (32-1-1, 15KOs) and Golden Boy Promotions to sign on the dotted line to move forward with the fourth defense of the WBC lightweight title he has held for more than two years.

Diaz comes into the fight with Olympic and championship pedigree.

The veteran southpaw boxer from South El Monte, California represented the United States in the 2012 London Olympics and previously held the IBF junior lightweight title, though his 13-month reign ended without a successful defense. Diaz lost the belt at the scale after missing weight ahead of an eventual twelve-round draw with unbeaten Russian contender Shavkat Rakhimov this past February in Indio, California.

Diaz has since gained retribution following a twelve-round win over Javier Fortuna this past July, agreeing to move up to lightweight in place of Ryan Garcia (21-0, 18KOs) who cited mental health maintenance in withdrawing from the fight. Diaz and Garcia were due to collide later this month, only for Garcia to suffer a wrist injury requiring surgery.

That opened the door for Diaz to make a run at becoming a two-division titlist, confident that his body of work has sufficiently prepared him for this moment.

“I feel like I’m at my prime. I feel like I’ve already taken all the steps I need to take to make it to this point in my life and in my career,” believes Diaz. “Taking fights with Andrew Cancio, with (former WBA titlist Rene) Alvarado, Jesus Rojas, Tevin Farmer, (WBC featherweight titlist Gary Russell, Diaz’s lone career defeat), Javier Fortuna. I’ve already fought those top tier fighters.

“I feel like Devin Haney, he’s a young fighter. He’s a hungry fighter and has a lot of experience… and ego to him where he wants to go on and put out tough challenges. I just feel like he doesn’t have the experience that I have. I feel like that’s going to be a key factor to my victory come December 4.”

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox