3 umpire situation

[Andy]

Was watching one of our State Championship games last night with a group of umpires and a situation came up that got us talking....

3 umpire system, no runners on base.

High popup to short left field, F6 is moving backward and makes the catch easily on the edge of the grass. U3 turned to watch the catch, but PU makes the out call and signal with no signal from U3.

The discussion was whether or not U3 should have been moving toward second base since there was no chase. My initial thought was that she should have been, but upon thinking a bit more, I can see why she didn't.

When the ball came off the bat, it looked like it was going to be a deeper fly ball that required a chase, by the time U3 read that the ball was in fact much shallower than that, her path to second would have taken her in front of F6 attempting to catch the ball and could potentially be a distraction, although U3 would have been well in front of F6.

Thoughts?