CARSON, Calif. – Turns out, it was Showtime … for “The Special One,” Kell Brook.

In a minor upset, Britain’s Kell Brook (33-0, 22 KOs), of Sheffield, England, won a battle of undefeated welterweights and the IBF world title with a majority 12-round decision over defending champion “Showtime” Shawn Porter (24-1-1, 15 KOs), of Cleveland, Ohio, Saturday onSHOWTIME from StubHub Center in Carson, Calif.