That's funny, case Ulti doing like same to Pay Pay LOL
But then again it's like battle of Brain vs Brainless, what is more important that Usopp created Nami's weapon, so this fight will be fair in all terms, case those two will come up with great plan and will defeat brother and sister pair.
Also this is great for develop of Nami and Usopp relationship, they really similar to each other, and maybe could called as brother and sister in some terms)
A jack that just fought an army of Sulong Minks and was visibly tired and injured. Not really the best feat if u ask me, that they needed to gang up on him in their strongest forms and it looks like they even needed some time.