Most of the boxing world was shocked by the brutal knockdown of former heavyweight champion Anthony Joshua by Daniel Dubois.

But one ringside observer took it harder than most: fellow British heavyweight Tyson Fury.

Fury scratched his head as Joshua lay on the canvas after the fifth-round knockout in the IBF world title fight. And as Dubois celebrated before a record crowd of 98,128 at Wembley Stadium — the largest ever for a fight in the UK — Fury shouted: "Listen, that's cost me 150 million [pounds]."

"Of course it has! He's f*****," Fury added, shouting toward Turki Alalshikh, the Saudi Royal responsible for bringing boxing's biggest fights to life with his immense financial backing.

"Turki, you'd better pay me now!"

Alalshikh, however, seemed far from too pleased himself.

During the broadcast of the event, the 43-year-old appeared to make a swift "cut" gesture to the camera operator as he stepped in front of his viewing position.

It was an understandable reaction from a fan of the sport desperate to arrange one of the sport's most highly anticipated match-ups: An all-British showdown between Fury and Joshua.

It was even more understandable from someone with a financial stake in such a contest, seeing its lucrativeness disappearing with every thunderous blow that slammed into the head of British boxing's most marketable asset.

Joshua was knocked down four times on his way to a fourth-career defeat to his younger counterpart, a brutal display of king-slaying that thrust Dubois back into the limelight that he seemed both destined to stand in and damned to be skirted by.

A boxer of immeasurable talent, Dubois has twice faced accusations of being not up to the brutal business of boxing.

Accused of quitting when taking a knee against fellow Brit Joe Joyce in 2020 — Dubois had a fractured eye socket and risked blindness, it later emerged — and then similarly going down when Oleksandr Usyk pummelled him last year.

In that fight, Usyk had earlier gone down himself, only for the crushing body shot to be controversially ruled a low blow.

The London-born and raised Dubois was consoled in the ring by Usyk after the match, the Ukrainian telling him that defeat is "not bad". 

"It's boxing … Daniel, you young. You can dream. Man, dude, relax."

Dubois, one of 11 children and brother of interim WBC women's lightweight world champion Caroline, comes across as shy and retiring, a man of few words and, perhaps short-sightedly, few marketing quirks to hang a pay-per-view off.

After Dubois's upset, Fury praised Usyk — who was also ringside in London and has beaten Joshua and Fury in recent years — saying, "You taught them both a proper boxing lesson. Fair play to ya."

Perhaps, in a world of brashness and bravado, boxing heads may need to start thinking outside the box.

Joshua moves to a professional record of 28-4 and is now at a crossroads that should, perhaps, result in his retirement.

He insisted after the fight that he would continue, while his promoter, Eddie Hearn said the prospect of a Fury fight was still available.

"We fancied winning tonight and facing the winner of Usyk vs Fury," Hearn said.

"Now we may end up fighting the loser of that fight if it's Fury."

Fury and Usyk meet in a rematch of their undisputed fight on December 21 in Riyadh. 

Usyk beat Fury by a split decision in May, becoming the first undisputed heavyweight champion in the four-belt era in the process.

Despite becoming undisputed, Usyk was forced to vacate his IBF belt to pursue a rematch with Fury, a belt now held by Dubois.

Fury, meanwhile, has a unification fight to focus on.

After signing to fight Joshua in 2021, only for Deontay Wilder to take the British heavyweight to court to exercise a rematch clause that led to the concluding of their spectacular trilogy, Fury will have a shot at Usyk to regain the heavyweight titles for a third time. 

The 36-year-old former unified champion was more prosaic about Joshua's prospects when interviewed later.  

"It's heavyweight boxing, s*** happens," Fury told FightHub TV — a motto that could be extrapolated to include the entire sport.

"You get knocked spark out. It could have been me. In the heavyweight division, it's what happens.

"What went wrong is what always happens in heavyweight boxing. A good right hand on the end of the chin, and that was it."