Even with everything aligned in Arozarena's favor, he was safe by a fraction of a second. As a pitcher, your goal there is to not get distracted by him, because the assumption is that he's not going to be crazy enough to go. And even if he does go, you're probably going to throw him out anyway. If you watch the full AB, you can see he made a bit of a false jump toward home earlier in the AB and got absolutely zero reaction from the pitcher. At that point I think he decided to go for it. Truly one of the more remarkable plays in recent postseason memory. About as beautiful as it gets!