Anthony Joshua set up a money-spinning January showdown with Deontay Wilder with a devastating seventh-round knockout of late stand-in Robert Helenius.
Joshua was expecting to face Dillian Whyte here until his fellow Brit failed a VADA test and Helenius stepped in on seven days’ notice.
And Helenius played his part here until Joshua found his range and despatched the Fin with a straight right hand that laid him out flat on his back.
With that job done, attention immediately turned to a potential showdown with Wilder, with Saudi Arabia willing to pay both men a fortune to fight there in the new year.
And Prince Khalid, the man with the money in the Kingdom, was a matter of feet from the spot where Joshua delivered the most violent full stop to this contest.
Eddie Hearn said: “It’s the fight we want. We have a three-fight plan. Helenius, Deontay Wilder and then Tyson Fury. That is the ambition.
“We believe he can go and beat Wilder. Skills Challenge are here tonight so we will try to close that deal over the next couple of days.
"We are looking at a January date and we are ready to sign for that date. Saudi Arabia want one of the biggest heavyweight fights of all time - and we're ready."
A lone violinist had played the Godfather theme tune as Joshua, in a long blood-red robe, marched from his dressing room to the stage. He seemed emotionless as he then made his way to the ring.
There was a time when an August Joshua fight in the UK would have certainly taken place in a stadium but his pull has waned without the belts. Indeed there were sections of the o2 curtained off with tickets unsold.
But there was still an electric atmosphere as Joshua entered the ring and hugged Derrick James, then turned to face Helenius who he had shared some heated words with at Friday’s weigh-in.
There had also been an argument over gloves on Friday when Helenius insisted that he was not happy with the Leone gloves that Joshua would be wearing and told Matchroom he wanted to wear the same.
The two sides had come to an agreement on Saturday afternoon and it was red Leone gloves - not Grants - that the Nordic Nightmare wore here.
And he got straight to work on putting them to use by firing a jab-cross-hook at Joshua. However the London man responded with a stiff jab.
Joshua was attempting to keep it long and land with two-pieces straight down the middle while the towering Helenius, upright and on the back foot, was always looking to step back and counter with the left hook. Through two rounds it was cat-and-mouse.
Midway through the third round, there was audible whistling and booing from the crowd, with the two men failing to produce any meaningful action. But it only spurred Joshua into life and the two-time heavyweight champion landed a crisp right hand right on the beard of Helenius which brought a cheer all the way back in the cheap seats.
They were on their feet again in the fourth when Joshua shuffled his feet forward and landed again with a big right hand but Helenius took it well and tied Joshua up.
The fifth was an eventful one as Joshua started by landing another big right hand on Helenius. But the Fin, sensing AJ’s confidence growing, decided to let his hands go more often and landed to both head and body in his best spell of the fight. But Joshua wrestled control back and hurt Helenius once more before the bell sounded.
But when the fight quietened down again in the sixth, back came the boos from the crowd. However, they once again turned to cheers in the seventh as Joshua detonated the finishing punch on Helenius’ chin which sent him down and out. Referee Victor Loughlin waved it off instantly.
As paramedics entered the ring with oxygen, Joshua jumped out and celebrated with family members on the inner ringside.
Joshua said: “Helenius has got talent, I had to figure him out. I think he can cause a lot of people some problems. Credit to him for saving the show.”