Teofimo Lopez lost his unified lightweight world titles to George Kambosos Jr in a huge upset in New York.
Hometown hero Lopez was cheered on by a packed out crowd at Madison Square Garden, but was dropped in the first round and ultimately beaten by underdog Kambosos.
Thousands descended on the iconic Manhattan arena to welcome Lopez back to the ring as the bout, which was initially set in February, finally took place.
But the Brooklyn native was down in the first round with a big Kambosos overhand right dropping the champion.
Lopez had flown out of the traps with venom, but was punished by Kambosos, who he later had on the ground with what was ruled a slip.
He recovered well and was back in control by the end of the second, hurting the Sydney native with a number of heavy shots in the third.
The pair had been harbouring serious ill will towards one another since their first press conference in April, for the initial June fight date, and it showed in their vicious exchanges as the fight wore on.
The rounds remained tight through seven, with the challenger looking comfortable in the ring with one of the pound-for-pound greats in the world.
But in the eighth, the tide appeared to shift for Lopez, with a huge flurry at the end of the round almost dropping the challenger.
He had the crowd on their feet in the ninth with an excellent shot that clipped Kambosos, and dropped the Australian in the tenth, turning the scorecards completely on their head.
However, Kambosos would not go down without a fight, taking massive punishment in the 11th before the bout was briefly stopped for the doctors to take a look at a cut on the champion's eye, and arguably winning the round.
The bout was taken the distance with an explosive 12th round, and a split decision decided the fate of the unified world lightweight titles, with the Australian stunning the New York crowd and taking home the gold.
It was a night of championship boxing in the Big Apple, with Kenichi Ogawa being crowned the new super-featherweight world champion after beating Azinga Fuzile.
Ogawa dropped Fuzile in the sixth round of their back-and-forth contest, before again putting him down twice in the twelfth and winning the unanimous decision for the vacant belt.
On the undercard, Zhilei Zhang stole the show with a vicious knockout win over Craig Lewis to return to the win column.
He had been held to a shock draw in February by the veteran Jerry Forrest, and got back to winning ways with a gruesome second round stoppage of Lewis.
The Chinese heavyweight was joined by boxer and model Ramla Ali, who went 4-0 in her professional career by beating Isela Vera.
She cruised to a four round decision win over the game Vera, who was returning to the ring for the first time since her debut in September 2020.
Raymond Ford also won his eleventh professional bout, stopping Felix Carabello in the eight round of their contest.
Ford was tested by Carabello throughout the bout, but won every round before the Puerto Rican's corner stopped the fight.
Elsewhere, Anthony Christopher Herrera knocked out Jonathan Tejeda in the second round of his debut, while Christina Cruz beat Maryguenn Vellinga by unanimous decision.