Andy Ruiz Jr looks the value to upset Anthony Joshua again

Was their first fight an aberration with AJ not himself? Or merely a Mexican demolition on a champion unable to cope with the fast hands and combination punching of an inspired challenger?

There no question that their first fight in June has been the defining moment of the sport in 2019. As heavyweight upsets go this was the biggest since Buster Douglas pole-axed Mike Tyson way back in 1990. A late replacement, the rotund (and in some quarters ridiculed) Ruiz Jr somehow clambered off the canvas in round three to shock the world. He dropped Joshua four times in total to completely change the landscape in the heavyweight division.

Yet despite the fairly conclusive manner of Ruiz's victory the bookies were quick to install Joshua as a warm favourite for the rematch. Rumours that AJ was hurt in sparring in the lead up to their first bout, or that he suffered a panic attack of sorts pre-fight, continued to swirl in the days after that jaw-dropping first loss of his pro career. In all fairness to Joshua he deserves credit for invoking the rematch clause. Plenty other guys would have ran from it. He's put himself straight back in the bear pit. Love him or hate him, one simply must respect his spirit to do this.

There are three heavyweight titles on the line again on Saturday night, but it feels like quite a bit more is at stake for the challenger. A convincing win and that first fight can be dismissed as a freak result and a semblance of order will have been restored in boxing's richest division. Another defeat though and the vultures that have been circling around AJ will pick his bones clean. He will be dismissed as a 'hype job' and the brand he has worked so tirelessly to create will lay in ruins.

It's a truly intriguing contest. 22-1 (21) Joshua the sculpted Adonis against the 33-1 (22) Ruiz Jr, a man who looks more like a Hispanic football hooligan than an athlete. A boxer who was previously ditched by promoters and trainers for being undisciplined against an Olympic gold medalist.

Whatever the narrative Sky or DAZN have been trying to spin in recent weeks, that first fight was no fluke. Joshua was not caught cold but was actually beaten to the punch time and time again by a boxer with faster hands. Ruiz saw his openings and he capitalised. The fact he is now champion should give him huge confidence too.

In the last few months there have been predictable question marks over whether Joshua can hold a shot? He was down multiple times against Ruiz Jr and never really looked comfortable from the moment he took a big shot to his temple midway through round three. The Briton can clearly punch himself and has some destructive KO's on his resume but could be gun-shy this time around against an opponent with clear hand speed advantages.

Those confident it will be revenge and not repeat feel Joshua just needs to stay patient and box from the outside. Yet can he show this kind of discipline? Be more compact defensively and thoughtful about his attacks? It's possible, and if he does he would have a real shout. However I cannot ignore the fact that Ruiz Jr looked the more seasoned fighter in that first contest, particularly when it came to in-fighting. Ruiz moves his feet well too and is deceptively nimble given his size. He can sit in the pocket and bang away but the way he controlled the distance against AJ first time round was impressive. The better man won on the night, so I am struggling to see why the bookies don't have this as a 50-50, pick 'em fight. Surely, given what we know, anything better than 2/1 about a Ruiz win simply cannot be ignored. Another imponderable regarding this rematch is the location. It remains to be seen how both men will react to fighting in the restrained, unfamiliar surroundings of Saudi Arabia. Throwing all the ingredients into the pot this is such a difficult fight to call, so a small play on Ruiz looks the sensible play.

To those still not convinced it's worth remembering that history is against Joshua too. The list of heavyweight champions who have been dethroned and then won an immediate rematch is not an exhaustive one. Indeed Floyd Patterson, Muhammad Ali and Lennox Lewis are the only fighters who have ever managed the trick in the long and chequered history of the sport. It's possible that Joshua joins that elite list this weekend. Possible, but not probable...

Betting: 5pts on Ruiz Jr to win at 21/10 (Paddy Power)