Josesito Lopez looks to upset Victor Ortiz

The powers that be haven’t made life easy for Riverside boxer Josesito Lopez.

The scrappy fighter now has the opportunity to make so many other powerful men’s lives uncomfortable Saturday night when he steps into his substitute’s role in a Staples Center main event against Ventura’s Victor Ortiz.

Lopez (29-4, 17 knockouts) was added to the Showtime-televised bout last month after Ortiz’s scheduled rematch with world welterweight champion Andre Berto was snuffed by Berto’s positive steroid test.

Ortiz (29-3-2, 22 KOs), a power puncher seeking redemption after his September defeat toFloyd Mayweather Jr., is supposed to win.

Ortiz weighed in Friday at 146.5 pounds, while Lopez weighed 144.8 pounds.

Showtime announced plans last week for Ortiz’s Sept. 15 super-welterweight title fight on pay-per-view against 21-year-old champion, Saul “Canelo” Alvarez, at MGM Grand in Las Vegas.

Showtime Sports President Stephen Espinoza called Alvarez-Ortiz a “dream matchup” Thursday.

“I was bothered by it,” Lopez, 27, said. “I feel disrespected.”

Ortiz promoter Richard Schaefer of Golden Boy Promotions said if Lopez beat Ortiz, he’d be part of a “contingency” plan for Alvarez.

“It’s a slap in the face,” Lopez promoter Ken Thompson said. “When you so obviously look past a guy, you inspire him to be his best.”

Lopez, 27, has found inspiration through boxing after growing up poor and seeing his father, Jose Sr., imprisoned in Texas more than eight years ago in a drug transportation case. Lopez has also suffered three narrow losses by decision since 2006.

“The way things have happened for him, it toughened him up,” Thompson said. “This is where he makes his big move in life.”

Ortiz is seeking his own boost after the loss to Mayweather in a fourth-round knockout. In that round Ortiz head-butted Mayweather, kissed him on the cheek to apologize, then let his hands down as the experienced champion belted him twice in the mouth to end the bout.

Lopez trainer Henry Ramirez said, “I think we’ve got a real shot. Ortiz is talented, but he’s shown he can fall apart mentally in the ring.”

“I’m very confident in myself,” Ortiz said. “I don’t need to prove anything to anyone.

“I’m very confident about this fight. I had eight months of work … You’ll see that Saturday night.”

Promoters say Saturday’s card — which includes a junior-welterweight bout betweenMexico’sHumberto Soto (58-7-2, 34 KOs) andArgentina’sLucas Matthysse (30-2, 28 KOs) — has sold an estimated 6,000-plus tickets.

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