Not since Kostya Tszyu's crushing win over Zab Judah in 2001 or Lionel Rose's defeat of Fighting Haruda at Tokyo's Nippon Budokan in 1968, has an Australian boxer scored such an impressive away-from-home victory.
"George's performance was up there with greatest Australian sporting achievements of all time," Fenech told Wide World of Sports in the aftermath of the fight.
"This is headline news. I'm watching now, he's not on any of the channels (leading news bulletins).
"Listen he's just done what nobody thought he could do. And I'm one of those guys. I said it was the hardest job ever."
While Tim Tszyu has grown into a media darling off the back of an impressive 20-0 start to his professional career, Kambosos' name was rarely mentioned in dispatches before the lead up to this fight. Granted he hasn't fought locally since 2017, instead choosing to take on the best in their backyards overseas. The new world champion's record laid out his champion qualities before he was one, but the recognition never came.
Leading into the Lopez fight, reports revealed the 28-year-old from Sydney's south had clashed with some sections of the Australian boxing media in the past, with suggestions that may have led to his lack of exposure. However, that should not get in the way of celebrating Kambosos' huge accomplishment when he returns home from New York, says Fenech.
"He's very outspoken. I've tried to have a talk to him once and he gave me a mouthful," he added. "You need the boxing people on your side.
"If this happened to anyone else, any other fighter in the world, they'd give them a ticker-tape parade when he gets home.
"I hope George gets one because he f---n deserves one. Write that.
"This kid deserves a parade."
Kambosos' victory was big. Really big. To travel to New York to take on the champion in his home state and to come away victorious rarely happens.
From what I can remember, the last fighter to travel to the United States for a boxing title fight was Jeff Horn in 2018, when he was cleaned up by Terence Crawford, who made a mockery of the Queenslander in Nevada to snatch his WBO welterweight crown.
Kambosos knocks down Lopez
Tszyu's stunning win over Zab Judah at the MGM Grand in 2001, making him the undisputed light welterweight champion, is certainly a contender along with Rose's gritty win in Japan.
Some of the conjecture online suggested Horn's 2017 win over Manny Pacquiao at Suncorp Stadium held more weight within the annals of Australian boxing history, but Fenech scoffed at such a claim.
"They want to talk about Jeff Horn and Manny Pacquiao," he said. "Horn fought an old man. George went into the lion's den and came out on top.
"George won it. No trainer, we could give everybody credit but George won it because George wanted to win.
"He had opportunities in the tenth round to let it slip. He could have said this guy is going to come out and kill me in the eleventh.
"But his mindset didn't let that happen. His mindset said 'I'm going to go and win the eleventh round' and he did."
There's no doubt Kambosos is now the most accomplished current Australian fighter, with several Aussies making their mark on the world stage.
Kambosos has three of the four lightweight belts, with the WBC regular belt the only one missing from his collection to become undisputed champion.
American Devin Haney holds the regular WBC belt, and has expressed interest in fighting Kambosos in the new year for the undisputed title, although he has to beat Joseph Diaz Jr this week to make it happen.
Others that are in the picture include impressive Americans Gervonta Davis and Ryan Grarcia at 135 pounds.
The Australian is a broadcast free agent and has plenty of flexibility when considering his next fight, meaning a fight on Australian soil could be on the cards.
"I think he's going to sit back, take a little time off and enjoy the victory," his promoter Lou DiBella told ESPN. "Then we're going to figure out the biggest fight we can make."
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