Work on your understanding its pathetic. Both sakura and hinata wouldn't last a second in battle with pain/nagato.
Your saying my understanding is pathetic shows your ignorance. Anyone who knows their fighting style knows that Sakura has much better chance against Pain compared to Hinata. She won't last long, but she'll last longer than Hinata. Plus, after gaining Byakugou seal and regeneration, she can survive and tank some minor attacks that Hinata will die against.
If only it's a open field then perhaps Sakura may have a chance but then we can argue that Hinata isn't going to sit idly by and allow Sakura to punch the ground when Hinata can simpily jump in mid air beforehand and use air palm which is completely unavoidable once you locked on target.
Hinata won't be able to land that well on crumbling ground, Sakura can take advantage of her lack of stability. Plus, Hinata being in air gives Sakura the chance to Shannaro punch her and Hinata can't dodge it.