Joseph Diaz Jr. will use South El Monte gym as motivation for Saturday’s fight

When Joseph Diaz Jr. walked into the gym at noon Tuesday, a short trip down memory lane began.

He first came to the South El Monte Community Center when he was 11 years old, wide-eyed and ready to use his fists. That triggered a big smile from the now 23-year-old. Hanging on the back wall of the dimly-lit room was a banner reading, “Home Club: 2012 U.S. Olympian, Joseph Diaz Jr.” That triggered a lot of reflection.

“Every time I come in the gym I look at that and it’s just more motivation,” Diaz said. “It’s just like, ‘Man, all that hard work actually paid off.’ My next goal is to become world champion, and if I keep working hard I can accomplish that goal as well.”

Four years ago, Diaz (20-0, 11 knockouts) used the London Olympics to kick-start a professional career that leads to Saturday’s fight against Victor Proa (28-1-2, 21 knockouts) at Fantasy Springs Casino in Indio. Diaz holds the NABF featherweight title, and is co-headlining an HBO Latino card also featuring super-lightweight Antonio Orozco (24-0, 16 knockouts) against Abner Lopez (23-5, 19 knockouts).

Diaz sees this fight and the Olympics very similarly: A chance to garner attention — this time from HBO to challenge the division’s top fighters on pay-per-view — and step into a bigger spotlight.

“That Olympic opportunity meant so much to my career, just as a way to build a fan base and then get Oscar De La Hoya and Golden Boy to notice me and want to sign me,” Diaz said. “Now I’m here and I have to win and deliver.”

De La Hoya built his reputation at the 1992 Olympics in Barcelona, winning a gold medal as a relatively unknown 19-year-old from Los Angeles. Diaz didn’t medal in London, but showed enough to get his first professional fight fourth months after the Games. That early-career path will become less common in the coming Olympic cycles, as the International Olympic Committee permitted professional fighters to compete in Rio.

See the most-read stories in Sports this hour >>

Diaz doesn’t support that decision, but is singularly focused on Proa. He thinks the 31-year-old counter-puncher will allow him to move around the ring, something Diaz is comfortable with but didn’t do as much in his last few fights, which he labeled as “brawls.” If Diaz proves he can excel on the move, he thinks he’ll be seen as a mobile power puncher who can vie for the division’s top belts.

That starts Saturday, when he’ll fight at Fantasy Springs for the sixth time. Bouncing around a similarly familiar gym Tuesday, Diaz stopped in front of a mirror and threw playful punches at his reflection.

The boxer laughing back at him is a product of the one-room gym and the Olympic banner on its back wall, and now has bigger steps to take.

“I just have come so far, when I think about London and everything before that, it’s like that was another lifetime,” Diaz said. “The stuff I learned then and the stuff I’ve learned since, I’m ready to be a big-time fighter.”

jesse.dougherty@latimes.com

@dougherty_jesse

MORE FROM SPORTS

Olympian carries family’s badminton dreams from Orange County to Rio

Rio Olympics won’t accelerate spread of Zika virus, researchers say

USA Olympic, Knicks star Carmelo Anthony holds forum in L.A. about recent tragedies in the U.S.