Joseph Diaz Jr. (L) faces off with Jayson Velez. Photo by Tom Hogan – Hoganphotos/Roc Nation Sports

OAKLAND, Calif. – Joseph Diaz Jr. fought in the 2012 Olympics in London. He fought in front of nearly 40,000 fans on the undercard of Canelo Alvarez-James Kirkland in Houston. Now, for the first time, Diaz fights on an HBO co-feature.

It’s just another step up in the career of the talented young featherweight contender.

“It feels like any other fight,” said Diaz, who faces Jayson Velez on the undercard of Andre Ward-Sullivan Barrera on Saturday at Oracle Arena. “I’ve been on these stages before, fighting in the Olympics, on TV, in front of a lot of people. I’m ready for these stages.

“I’ll have butterflies going into the ring (Saturday) but once I’m there I’ll have tunnel vision. My only focus will be Jayson Velez. And the only person I’ll hear is my cornerman, my father, Joseph Diaz Sr.”

Diaz (19-0, 11 knockouts) has steamrolled over almost all of his opponents. Not so for Velez, who is only 1-1-1 in his last three fights. The Puerto Rican drew with then-IBF featherweight titleholder Evgeny Gradovich in November 2014 and, in his last fight, he lost a decision to Ronny Rios.

Diaz doesn’t expect to face a damaged opponent. In fact, he expects Velez to be as determined as ever.

“I think he’s going to be extra hungry because he’s trying to bounce back,” Diaz said. “I don’t think he thinks of himself as an ‘opponent.’ I think he still sees himself as a world title contender. And he wants to prove it.

“I had a really great camp, though. I know my skills, my capabilities. My father and I worked on everything I’ll need. I’ve been working with my strength and conditioning coach, Darryl Hudson. So I’m quick, strong, elusive, ready for anything Jayson Velez brings to the table.”

He’d better be if he wants to make a strong statement on the premium network, which is his goal.

“Fighting on HBO is a dream come true,” he said through a wide smile. “Ever since I was a kid, I wanted to fight on HBO. Champions are made on HBO, champions fight on HBO.

“This is a great opportunity to showcase my skills. Hopefully they’ll like me and I fight on HBO again. I want to keep making a name for myself.”

Diaz has spoken about the bigger picture, which could include elite 126-pounders like Vasyl Lomachenko, Leo Santa Cruz and Gary Russell Jr. That seems to be the trajectory he is on.

“And maybe Ronny Rios,” Diaz added, referring to his fellow Los Angeles-area fighter.

“That’s possible,” said Robert Diaz, matchmaker at Golden Boy, which handles Diaz. “Let’s get past this fight first, though, huh?”