The fight at the Staples Center in Los Angeles was won by the Londoner in a split decision, with two of the three judges siding with him.
The pair first fought last year in Manchester but a “majority draw” was declared after six rounds.
But this time the Brit came out on top after the American was deduced two points for an illegal shot.
“It doesn’t feel like a loss, I know what a loss feels like,” he said afterwards. “Something tells me I’m going to be alright.
“Maybe its because I’m not a boxer but something also tells me that if I have another boxing fight, we could probably sell out another Staples Centre and get a decent amount of downloads on DAZN, especially if its from the right person.”
He added: “Yeah, I’ll be good. Plus, in the face of adversity rises a titan.
“I really thought about this, if Joe Weller had won the first fight against KSI, something tells me Joe Weller wouldn’t be as well off as he is now.”
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