Anthony Joshua steps into his dust-up in the dunes in the greatest challenge, mentally, the 30-year-old will ever face in his career against Andy Ruiz Jr.

Humbled in New York six months ago, on his United States debut, Joshua must now show, after being dropped four times and stopped, that he can make the adjustments to re-write his own script in the history of the heavyweight division.

There is so much on the line for Joshua in his 24th fight, and in a high-risk, high-reward (£70million purse) fight, there is the genuine chance of redemption, with both the wider public, and boxing insiders.

Boxing fans in for a classic

Joshua must use his height and reach advantages, and keep behind his jab, protect his chin, and stay long for round after round, clinching and leaning on Ruiz when in close. The toughest mental test will be for Joshua doing exactly that, because his propensity as a boxer is to want to get into a firefight. It got him out of trouble in the Olympic final with Roberto Cammerelle, against Dillian Whyte after he had been rocked by a left hook, and against Wladimir Klitschko, when he showed great survival skills, albeit against a great, and ageing, champion.

This week, I have spoken with the great American heavyweight George Foreman, and Frank Bruno – who is working alongside me on the William Hill live stream on Saturday night – and both men believes Joshua should employ the same tactics Muhammad Ali used in his rematch with Leon Spinks in 1978 with “a jab, jab, grab technique” as the Briton attempts to reclaim the IBF, WBA and WBO belts from Andy Ruiz Jr, and become a two-time heavyweight champion of the world.

Foreman’s advice to Joshua is straight out of an old school boxing textbook. “The good thing about Anthony Joshua is he has so many options — with his height, reach and punching power. Muhammad Ali style against Spinks, where you just jab, jab, then hold. Joshua can do that for 12 rounds. He don’t need to prove anything to us. Go out there and win every round. Don’t go for the mix up, that’s where Ruiz may have the edge. Don’t put your head down, like a giraffe… that’s when AJ is vulnerable – when he spreads his legs.”

Bruno concurs, as do I. “He needs to use his athleticism and break the guy down, like when he fought Parker. He boxed his ears off and done it neatly. I think he should watch the Parker fight and hold him when he can. He can win as long as he can play it cool and has patience; nick a few rounds, and don’t get into a war, no macho s— with this guy, because that’s what Ruiz likes. I think the jab is key in the fight because he’s got longer arms than Ruiz and he’s taller than him.

He’s got all the advantages for him to use the jab and movement. He can’t be too brave, trying to prove himself in a war. There’s not need for that. Box him and break him down. Hopefully be victorious. Either do a 12-rounder or stop him later on. But Mexicans are very tough.”

I agree with the strategy, and secondly Joshua’s mental strength and self-belief will grow if he can ease through the fight without being in trouble. The memory of those knockdowns will also fade, with growing confidence, yet Joshua cannot afford to be overly gun-shy. As Bruno told me: “The knockdowns from the first fight will definitely play on his mind. He’s got to start positive and use his athleticism and fitness.”

And what of Ruiz? From my corner, Ruiz will have made few adjustments, but he will feint more to get on the inside, and let those dangerous hooks go. When Ruiz is in range, he will let fly and punch with Joshua. He knows he may have the upper hand in this area, with faster hand speed and now, a growing self-belief. But Ruiz will be patient, too, and having a stealth tactic and waiting for this moment could pay off for him once more. His body language, confidence, the New York Knicks shirt, all his moves have been smart in the build up.

Manny Robles, Ruiz’s wise old trainer, told me this: “Joshua will be mentally scarred. I don’t think it’s that hard to figure out. It does play on your mind. Joshua can come into the rematch in great physical shape, but mentally? Will he be there? Will he exchange with him? It’s going to happen. He can’t box all night. A lot of people think Joshua’s going to come out and try to box. Try to use his length. He did that in the first round at MSG. But you can only box for so long. Eventually Andy is going to get in there and work that body and that head. How is Anthony Joshua going to react when he gets hit? We all know what we’re working with with Ruiz. He took some good shots in that fight and he took them well. He got knocked down and got back up. He took a few more shots after that and took them very well. On the other hand, Joshua didn’t react well. Not only that, speed equals power. I don’t think Joshua has fought anyone this quick. We proved the world wrong. We’re planning to do it again. I know we’re not the favourites again, but that doesn’t matter.”

In other words, Andy Ruiz just needs to be Andy Ruiz. Be himself, be comfortable, be the boxer with the longer record and greater experience. The one who shocked the world. The first Mexican heavyweight champion of the world. Foreman predicts that Joshua “is going to go out there and box. If there’s going to be a knockout it’ll be when he decides he has three minutes left and this guy can’t reach me. I believe he’ll win that fight in 12 rounds.” Andy Ruiz Jr. is 66/1 to claim a KO in round 12.

Bruno hopes Joshua does it for the future of British boxing, and sees the same gameplan.

But they all acknowledge the danger of Ruiz.

Can Joshua do what Lennox Lewis did against Hasim Rahman in 2001 and claim a fourth round knockout (16/1), or what Muhammad Ali did to Leon Spinks in 1978 and claim a Unanimous decision (9/2) or what Floyd Patterson did in the return bout against Ingemar Johansson in 1960, at the Polo Grounds, New York? They are the only three men to win back the world title in an immediate rematch.

Patterson regained the heavyweight championship of the world from Ingemar Johansson after being knocked down seven times by the Swede in their first fight. In the rematch, Patterson knocked Johansson out to become the first man in history to regain the undisputed World Heavyweight Championship. Johansson lay unconscious for five minutes before he was helped onto a stool.

That is the image Joshua will dream is beamed around the world from the Middle East on Saturday night. But it will depend on how Joshua fights and keeping a strong mindset. If, as conventional wisdom suggests, AJ keeps it long, and uses a strong jab, his height and reach advantages, the dunes could bring good tunes for the Briton. But he will have to keep his nerve, and stick to the plan. There will be psychological issues to overcome from that first fight. But this remains a very intriguing fight. Joshua on points, or late stoppage.

But if he gets into a firefight early, it’s 60/40 Ruiz.

Gareth A Davies prediction: Joshua victory on points (7/2) or 11th Round KO (40/1).

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