Despite giving away three inches in height, four in reach and nearly 20lbs in weight to Joshua, the superior ringcraft of the ex-undisputed world cruiserweight champion was there for all to see in his unanimous decision win.
The 34-year-old's stunning triumph in just his third heavyweight bout in an electric atmosphere created by more than 66,000 fans at Tottenham Hotspur Stadium carried on his love affair with the English capital.
Usyk collected Olympic heavyweight gold nine years ago the day before Joshua topped the podium in the division above and admitted even his latest success pales in comparison to what he achieved in 2012.
"London is a really lucky city for me but not a single professional victory can be above an Olympic gold," he said, via a translator.
Usyk stretched his perfect professional record to 19 wins from as many contests. The last 10 have been staged outside his country, while several world title fights have been held in his opponent's backyard.
He may wear a moniker of the 'Road Warrior' with pride but, with Joshua expected to immediately invoke a return bout after being dethroned, Usyk was asked for his venue preference.
"I would love to have the rematch at Olympiyskiy Stadium in Kiev," he replied.
Joshua's promoter Eddie Hearn seemed to pour cold water on the suggestion and hinted any second fight would likely be back in the UK.
"We will work together to maximise (the income), Ukraine is very unlikely," said Hearn. "I think it will be international or the UK, I would think it would be in the UK."
Usyk produced one of the finest displays of his professional career in north London and was rewarded with scorecards of 117-112, 116-112 and 115-113 – although Hearn said afterwards Joshua was up after eight rounds, only to lose the last four with each of the judges as his swollen right eye started to impact his vision.
Usyk said: "At this point it is the biggest fight in my career – but it wasn't the hardest one."
He was promptly asked who his toughest opponent was and, perhaps in an indirect reference to WBC title-holder Tyson Fury, Usyk replied: "I cannot say but, most likely, it's ahead of us."
It was the collapse of a fight with Fury that led to the WBO ordering Joshua to take on mandatory challenger Usyk.
Hearn said: "I think you need to credit (Joshua) because he could have swerved that fight easy and maybe we should have, but that's not really what he's about. You've got people who will take easy options and you've got people who will choose to fight everybody and the latter is AJ."
This was the second defeat of Joshua's professional career but Hearn believes it is not as harmful as the first he suffered in June 2019, a loss he avenged in an immediate rematch six months later.
"Weirdly, it's a lot easier to take because you know how good Usyk is and so you know there's a chance you can get beaten," Hearn added.
"The (first) Ruiz fight, we were probably a bit naïve at the time, almost walking on air, that AJ would just steamroll through everyone and that was a bolt from the blue you saw he couldn't get over for weeks.
"Here, you just say 'it's sport' – he got beaten by the better man, what are you going to do about it? Dust yourself down, improve and try to beat him in the rematch. That's all you can do."