Brian Norman Jr. considered what he was up against: Fighting in the hostile hometown of come-forward, unbeaten fighter Giovani Santillan with nothing less than a welterweight world title on the line.

Norman (26-0, 20 KOs) mulled sticking with a boxing-oriented fight plan. He felt he could win by doing that, but he’d be risking the perception that Santillan would be viewed as the aggressor by judges perhaps swayed by the hearty cheering of Santillan’s fellow San Diego residents.

Or he could fight fire with fire.

“We kept thinking if we keep moving, it’s going to tap into the idea we’re running from him, and make him press even more,” Norman Jr. (26-0, 20 KOs) told BoxingScene Monday.

“So let’s go to the fire zone, let’s see what kind of fight he can bring, see how hard it is. So I can do the blazing and press him.”

The strategy was hitched to Norman’s straight right hand, which cut Santillan, marked him up and even staggered him as ringside observers looked on in surprise.

“Right down the pipe – I kept seeing (the openings), so I kept letting it go,” said Norman, whose roaring cornermen shouted down the muted supporters of Santillan (32-1) inside the Pechanga Sports Arena.

After the sixth round, Norman was aware from scouting Santillan that he tends to fatigue during the second half of the bout. So feeling he was ahead on the scorecards and had taken the best of his opponent’s pressure, he said he felt Santillan’s “last hoo-rah,” with heavier punches sent with the message, “hopefully, this will calm you down.

“I didn’t calm down … and then I sent him down,” Norman said. 

Norman, after badly staggering Santillan and appearing to break his nose, dropped him earlier in the 10th round and then uncorked a vicious right uppercut that some have said may contend as knockout of the year.

Santillan’s already bloodied nose erupted and he crumbled to the canvas.

Punctuating his savage approach, Norman kneeled by his fallen foe and stared deeply at him – a response, he said, to spending the whole night feeling like he was Public Enemy No. 1 in San Diego.

“We had been strictly working on that one shot all camp – a simple left hook and then, boom!” Norman said. “I let it fly. I know when I nail that shot that clean, you’re going down.

“The crowd had really got me. I have nothing against Giovani. But I was in San Diego, everyone was booing me. Even before the knockout, I could still hear the shouts of ‘Gio! Gio!’ So I felt like I was the villain that night. I went into it and stared him down, (stared down) the energy I had been feeling from the crowd.”

The victory made Georgia’s Norman the WBO interim welterweight champion, positioning him to elevate as full champion after current champion Terence Crawford fights for the WBA junior-middleweight belt Aug. 3 in Los Angeles.

The expectation is that Crawford defeats the current WBA 154-pound champion Israil Madrimov and then relinquishes his welterweight belts, making Norman the full champion and one of only four world champions from Georgia. Among that group is former heavyweight champion Evander Holyfield and the late former two-division champion Vernon Forrest.

“I definitely feel like a champion,” Norman said.

Norman’s manager, Jolene Mizzone, said she’ll meet with Norman promoter Top Rank and see what officials have in mind next for Norman in a division that counts Jaron “Boots” Ennis (IBF), Eimantas Stanionis (WBA regular) and Mario Barrios (WBC interim) positioned as recently undisputed Crawford’s other replacement champions.

“We’ll see what our options are,” Mizzone said. “It’s so premature right now.

“I want him to enjoy this. A 23-year-old went into somebody else’s backyard and, in the last minute, the fight was made an interim championship. That’s a lot of pressure. Let alone that night. Brian proved the best revenge is proving a lot of people wrong.

“He was focused round one through 10, and had a game plan.”

Norman said he spent his life dealing with stacked odds.

“A lot of people doubted me, it was stacked against me,” Norman said. “I love when it’s like that. Because I had nothing to lose.”