I didn't see this incident so just a generic opinion. We've seen what happens when the pitcher gets hit with a linedrive. Those balls are hit hard no matter where they go. There has been talk about expanding the area covered by netting - but some fans have resisted or that's what MLB has said. There isn't time to react even if you're watching the play - once screening is up people are not going to notice it. I think Shitifield is one that expanded the screen - after Zim was hit by a foul ball, YS put screening up in front of the dugouts. Not sure just how far it should because any foul ball into the stands can be a 'deadly' missile - I'm talking from experience.