Buster Posey had no idea where a popup went off the bat, but figured it out just in time

One of the most helpless feelings on the diamond has to be that of the catcher when a baseball is somewhere -- but you don't know where. 
This scenario can play out on wild pitches, passed balls, popups, and so on. It can be a bit of a confusing time, for sure. Buster Posey certainly had an adventure in the sixth inning of Monday's Giants-Padres game at Petco Park thanks to a few different things happening at once. 
Christian Villanueva swung at the 3-2 offering from Reyes Moronta with the runner on first taking off with the pitch. Villanueva fouled the pitch off, his bat clipping Posey in the left shoulder area on his backswing. This probably hurt, so Posey stood up to take a stroll behind home plate and shake it off. 

The problem? The ball was live, and was right above him in the air on its way back down to Earth. He didn't know that, though, until Moronta yelled and gestured and Posey somehow figured it all out in time to make the play and retire Villanueva:

Got all that? It was a bit messy, but Posey got it done. Catchers are tough.