Board Thread:Questions and Answers/@comment-39718735-20200819093838/@comment-39718735-20200819183945

Yeah it's probably just that. Since Johnny was suddenly surprised in an instant. He's not perfect to predict where THE WORLD would appear. He probably shot that nail on pure instinct.

On the other hand, I'm now totally sure Johnny's plan was to attack Diego from the ground from the beginning: we can see the nail shot towards Diego (before he stopped time) is spinning even in stopped time yet Tusk didn't appear at all. When Johnny shot at Valentine Tusk ACT 4 appeared right away, even before the nail was shot.

I'd say that was the giveaway that made it clear for Diego that he was gonna summon Tusk from the ground later.