George Kambosos Jnr overwhelmed Teofimo Lopez with a relentless onslaught to become the new unified lightweight champion by split decision after a dramatic battle.
The Australian floored Lopez in the opening round and was then dropped himself in the 10th, but his sustained assault earned a stunning victory with scores of 115-112 and 115-111, while a third judge scored it 114-113 to the Brooklyn fighter.
Lopez's reign as one of the sport's elite champions was short lived after he defeated Vasiliy Lomachenko last year, with Kambosos Jnr pulling off a sensational win in a bout that had been rescheduled on numerous occasions.
A straight hand had sent Lopez to the canvas as Kambosos Jnr claimed a knockdown in a fiery first round at Madison Square Garden in New York.
Lopez struggled to contain the determined Kambosos Jnr, who fired back with flurries of punches as they traded shots in the frenetic early rounds.
Kambosos Jnr shrugged off a string of right hands in the ninth, answering with a big left hook, and he quickly overcame a knockdown in the 10th after Lopez landed a chopping right hand.
A cut opened over Lopez's left eye in the 11th, briefly halting the action, but Kambosos Jnr resumed his tireless attack until the final bell to earn a momentous triumph.