If you bet on AJ to win the fight whether through decision or KO, you will only get 1.44 odds, I think that's too cheap.
Maybe you'll consider betting on AJ to win via decision @ 5.40 because he might not be too confident in this fight trying to knock out the champ, maybe he will just use his length and consistently score throughout the 12 rounds.
AJ by decision @5.60, that's my bet. I'm also thinking that Joshua will just use his jab in this fight to win, which in the first fight is effective and might soften Ruiz in the later rounds. This might be a boring fight as i see Joshua will not slug it out with Ruiz. Jab, jab and clinch if Ruiz would go inside, that would be the game plan of AJ.