Joshua has reigned twice as world heavyweight champion and has earned astonishing riches from the sport, but at the age of 34 still yearns to be 'Undisputed' and when all is said and done will want to be remembered as the best of his era.
To be in that conversation he knows he will need to beat Ngannou and then beat the winner of Tyson Fury v Oleksandr Usyk, who box for all the heavyweight belts on May 17.
AJ is on a three-fight winning streak - after rebuilding from consecutive losses to Usyk – but in his heart of hearts will be aware there is nowhere to go should he lose this weekend.
No belts are on the line but all the hard graft he's put in since turning pro in October 2013 hinges on the outcome of this fight. The betting line sees him as a 2/7 favourite for victory, with Ngannou a 7/2 shot and the draw priced up at a meaty 33/1.
The 27-3 (24) Joshua seems to be in a good place again and looks a dangerous, offensive fighter once more under new coach Ben Davison.
In Ngannou he faces something of an unknown quantity, a fighter with a 0-1 pro record but who, despite those numbers, is arguably the hottest commodity in the division. That is because of his spectacular boxing debut in October 2023.
The sight of Ngannou standing over a decked Fury in round three of their fight was one of the sporting images of last year. However, he offered much more than that knockdown against Fury and the African had plenty of success all night, exhibiting heart, skill and counter-punching nous before losing a contentious decision after 12 rounds.
That performance was enough to see him land a spot inside the top 10 of the WBC heavyweight rankings and so here we are. Ngannou is going to pick up the biggest payday of his combat sports career, but you get the feeling he is not just here to make up the numbers.
The Cameroonian may be a novice when it comes to boxing and somewhat rough around the edges, but he is a star of the MMA world who once upon a time was the UFC heavyweight champion of the world.
His story is remarkable. Desperate to help his struggling family as a child, Ngannou began to work in the sand mines in his homeland - and did so for seven years – during a time when most kids his age would normally be going to school or playing FIFA.
At 37 it is debatable whether there will ever be enough time to smooth those rough edges out, but 'Team Ngannou' will be banking on their man's power and gas tank to get the job done in Saudi.
He is a thickset, powerfully built athlete and it was remarkable to see Fury struggle to put a dent in him when they met last year. If AJ hits him with his best shots, and Ngannou does not move, the Englishman could be in for a very uncomfortable evening.
AJ holds all the aces when it comes to movement and boxing ability, but Ngannou's raw power is for real and that is why this fight is intriguing.
Joshua could keep things at range and box his way to a tidy decision. However, there will be a temptation to fight on the front foot, put it on Ngannou and beat him in much better fashion than great rival Fury managed.
If he does that though, Ngannou could start to dictate with the elite inside game he honed in the UFC. There is also the danger of AJ walking onto one if he is too aggressive.
Educated pressure should be the tactic, but under Davison Joshua looks more like the destroyer who lit up the division on his way to his first world title success. Once overly reliant on his own brute strength and power, AJ has displayed nuances and maturity that were absent earlier in his career.
It is undeniable that under American trainer Derrick James, he looked a fighter who was tentative and caught between two styles. Davison has, to use American parlance, brought the 'dawg' out in him once again and he looks a much better fighter when he is on the front foot in seek and destroy mode.
Tactics will be crucial here. Joshua will not have faced anyone quite like Ngannou, who due to his MMA background does not really have any sort of classic boxing style. It was a puzzle Fury struggled to piece together, and Ngannou had some real success when counter-punching in that fight.
Responding to Ngannou's comments about going for the knockout during a media day recently, Joshua said: I'm optimistic and I think, 'brilliant, I want that'. I want someone in front of me who thinks they can knock me out.
"But let's see how good they really are. I want to be right in front of them, making it difficult for them to achieve their goal and see how much they really want it."
Boxing at range and using the jab is the most risk averse strategy for the Englishman in this fight, but that is not how he has boxed under Davison so there is a danger 'Team Joshua' may overthink it. Tactically, do they box to his own strengths, or try to negate Ngannou's?
When buzzed, Joshua often elects to fight fire with fire, and while that should make for an exciting fight, it leaves the door open for Ngannou to land something big.
Both men are respectful and both are warriors. Joshua is very media savvy, but at his core he loves to fight and he also has a mean streak. Publicly, AJ is making noises that he will be going for a KO/TKO finish.
"I believe I can knock him out," Joshua told Sky Sports recently. "Definitely. I would love to knock him out and make a statement."
Joshua to win by KO/TKO is priced up around the 4/7 mark, but that line has moved quite a bit in recent weeks from around 3/10, suggesting that gambling sharps are not convinced he can get Ngannou out of there.
The Cameroonian has never been stopped. Stipe Miocic had him in trouble in their exciting UFC heavyweight clash, but Ngannou rallied and stopped him soon after.
People talk about the insane power, but Ngannou's chin is underrated and he can take a shot. Fury hit him with some heavy artillery in October and he just kept trucking forward.
He has never been dropped or stopped in a top level fight, and can hear the bell again in this one so punting Joshua wins by decision or technical decision looks a smart play at 4/1.
Tip: Joshua to win by decision or technical decision at 4/1 (Betfair/Paddy Power/Skybet)
