'The Emperor' proved the doubters wrong by becoming the first man to defeat Lopez Jr since his loss to Sofiane Oumiha during his days as an amateur.
Kambosos Jr, 28, celebrated with his father in the ring after beating Lopez by split decision in Las Vegas.
But before the 28-year-old Sydney warrior clashed with the American a couple of days ago, they spent time in each other's company at the press conference ahead of Jake Paul's fight with Ben Askren.
And the Australian insists Lopez allowed his emotions to get the better of him and that led to his loss in their first fight at the weekend.
“My presence and what I did in that fight and that game plan, and the mental games I played and psychologically breaking him down months and months ago - I believe I broke him down when we had that press conference [in April], originally on the Jake Paul vs. Ben Askren fight,” Kambosos told MMA Fighting.
“The way I brought myself to that fight and what I’d done in the rounds, and especially scoring that beautiful knockdown, which I said I would - I said I’d catch him early; if I don’t put him to sleep early, I will catch him and hurt him - that’s what changed the fight.
“I believe he was concussed through that fight, that’s what changes a fight. Not what Lopez didn’t do. It’s what I did throughout them rounds. And I broke him down.
"I could fight him every single day, twice on Sunday, and he would not beat me. I would beat him every time, and it’s just going to get worse and worse, but I know he wants nothing to do with me now.”
Kambosos doubled down on those claims as he insisted Lopez was made to pay for taking his eyes off the ball.
He later added: “Look, I just say it the way it is, right? I chip away at certain things. I spoke about his weight issues to make the weight, his sacrifice and dedication to the sport.
"I felt like he was enjoying it too much, enjoying the bright lights, and that rattled him, that got under his skin.
"But the most important thing is when we faced off and went eye-to-eye, that’s when you really see what a man is made of.
“When I looked inside his eyes, I saw that he was soulless and there was fear there. And when he looked inside my eyes, he saw that, ‘This Kambosos from Australia who shouldn’t be here, who should be taken out in a rout, is actually here to fight, has got no fear. He’s coming to take everything off me.’
"And I think that stuck with him for a very long time, and it went the way it was meant to be.”
As for what's next, Kambosos wants to bring the belts back to his home country of Australia.
Kambosos has boxed overseas seven times in a row, including an entertaining scrap against Lee Selby in October of last year after signing with boxing promoter Lou DiBella and his DiBella Entertainment stable.
“One-hundred percent,” he continued. “I’ve had to really go into the trenches, the backyards. Now this is two former world champions and an undisputed champion, all in their backyard, in my last three fights.
"And time after time, proving the world wrong. Being the underdog in all of them fights, but still standing.
“I haven’t fought in Australia since 2017. It’s truly my time to go back home, fill out a stadium of 80,000 people, and bring something back special to Australia, defend all my belts, all these beautiful belts.
"Because again, they’re my belts, but they are Australia’s belts as well, and they deserve this as much as I have them.”News Now - Sport News