As we know, the tortoise defeated the hare in a stunning upset. My question is, what if the tortoise had granted the hare a rematch? Would the hare have learned from his mistakes to reverse the result, or would he have been too mentally crushed after the previous defeat? Can Anthony Joshua learn anything from this for his upcoming fight?
I think the question you're asking is who we think wins on Saturday. Please correct me if I'm wrong. I got Ruiz in 9. Joshua will try and make some adjustments, and fight more cautiously and defensively with his jab and size, but ultimately isn't good enough to stick it out till the end. Ruiz will also have had a full camp and be even more confident than normal.
I think Joshua has sort of learned his lesson. I think he wins, possibly by decision, while having a few uncomfortable moments on the way.
I'm favoring Joshua so long as his mind is in the right place, but who knows what Ruiz can do with a full camp this time around. Joshua better be motivated
This fight is a bit of a pick em situation, since we don't have full evaluation of the context. I'm going with Ruiz to stop Joshua again, as @George Crowcroft said. He provides stylistic problems that I don't think Joshua will be able to solve, especially with only 6 months thereabouts, such as his adept usage of parrying, his controlled manner of being the shorter man (which always bothered AJ) and his hand speed alongside his chin. AJ simply doesn't have the 'finesse' and boxing instinct to avoid him for 12. I actually think he should go all out for an early KO on Ruiz instead.
Here's the catch, there's no tortoise or hare in this scenario. It's a natural advanced innate skillset vs. decent learned skillset. 9 times out of ten, the skills will end up paying the bills, especially when the guy with the advanced skillset also has an iron chin.