Teófimo López stunned Vasyl Lomachenko in Las Vegas to become the unified lightweight champion.
It was an astonishing performance from the 23-year-old as the judges scored 116-112, 119-109 and 117-111 in his favour.
Not only has he overcome arguably the best pound-for-pound fighter in the world, he did so with an exquisite display that made a mockery of claims he would struggle at 135 pounds.
Attention now turns to who López will fight next and he wasted no time in calling out Devin Haney post-fight.
Either way, heavyweight legend Mike Tyson insisted his fellow New Yorker is now "the man to beat".
"Brooklyn was definitely in the house tonight. Lopez is the man to beat. Another Brooklyn champion. #LomaLopez"
López had gone into the bout with a record of 15-0, including 12-0 knockouts. A formidable opponent, but nobody can have predicted the extent to which he stifled the normally artful Lomachenko in the first half of the fight.
Lomachenko's supporters can dismiss the result as an aberration and he did improve markedly in some of the later rounds.
It was that rally that led to his angry reaction after his opponent's hand was raised, the Ukrainian storming out of the ring and questioning the scoring of the later rounds.
At 32, however, his previous record shouldn't be dismissed, but López will be confident of usurping his throne on a more permanent basis.
It's easy to see why the world of boxing is raving about its new champion this morning.
"What a fighter! You did exactly what you told me you were gonna do. Enjoy the moment."
While the result has sent shockwaves through most of the division, one man who saw it coming was Floyd Mayweather.
The Money staked $6,500 on the underdog, earning a return of $20,000. Small change to the 43-year-old, perhaps, but a huge show of faith that was rewarded.
It'll be fascinating to watch how López progresses from here.News Now - Sport News