That's true, but pressure is not always a bad thing. It did work for him pretty nicely in a fight against Fury. Him getting more confident could result in becoming too reckless or overcommitting and getting countered, but hopefully his mma experience will prevent that.
Looking at it from other perspective, he potentially have more in stake right now. The first fight was probably planned as a one off thing, but since he performed surprisingly well, he now could be fast-tracked into being in the top of the top in boxing. But if he gets ridiculed by AJ, then it would be obvious that the first fight was just a fluke and his boxing career could be over.
I think there's more on the line for AJ though. Ngannou isn't expected to win, and shouldn't on paper, but if AJ actually loses this fight then that seriously knocks him down the pecking order not to mention embarrasses him. AJ has got himself back on track to soon challenge for the belts again but a loss would be devastating. AJ even proclaimed "Every opponent me and Fury have in common, I've knocked them out" recently, but means nothing if Ngannou flattens him. However, if AJ can knock down or stop him then that puts him in front of Tyson with something he couldn't do. AJ really needs this win to get a one up of Fury and sets the fight up between them nicely.
These two fighters are now on top of the rank because of their wins against their respective opponents and the two are possible contenders for the winner in the Fury - Usyk fight in case the winner of the Joshua - Ngannou can't agree on the terms.
Parker is my favorite fighter to win against Zhang, I am more impressed by how he beat Wilder than Zhang beating Joyce, but he needs to be careful Zhang possesses a very wicked left straight and he has a good lateral movement.
Parker was impressive but Wilder seemed off to me. I think Zhang will either win by KO or Parker on points, but I think Zhang should get a KO. Joe Joyce got a KO against Parker and Zhang absolutely battered Joyce twice and was the first to do so.