Source: Referee.com April 4, 2018
When the strike zone disappears
Any fast-pitch softball umpire is familiar with the slot position when working a game as the plate umpire: assuming an approved stance behind the catcher, aligned slightly inside the inside corner of the plate and outside the perimeter of the strike zone. The rationale for this position, as explained in the various softball organizations’ umpire manuals, is to enable the plate umpire to see the entire plate and the ball as it moves from the pitcher’s hand to the catcher’s glove and to be able to accurately judge whether the ball passed through or out of the strike zone.
But as any umpire knows from game experience, being able to see the plate and strike zone from the slot can become more complicated by the positioning of the catcher and/or the batter. Sometimes the physical size of the catcher and batter can make it more difficult to achieve an unobstructed view from the slot position. Or perhaps it is a catcher who throws left-handed and lines up differently than a right-hander. If the catcher tends to raise from her crouch as she receives the pitch, she can interfere with the umpire’s view at the last instant.
When these situations come into play, the umpire often must make adjustments to maintain an unobstructed view of the strike zone. Here is some insight for how to ensure ball-strike calls remain consistent regardless of what the batter or catcher does.
You can’t call what you can’t see. If the catcher blocks the plate umpire from seeing an inside pitch, it’s a ball. If you must, explain it (the catcher’s movement) to the coach.
You must be able to keep the strike zone in perspective, especially the importance of positioning your head at the top of the strike zone in relation to the batter when going to the set position in the slot. When the batter or catcher is squeezing the slot, one thing you can do is look over the catcher to see the delivery of the pitch. You have now raised your view of the strike zone, so quickly glance at the outside parameters of the zone and mentally make the adjustment.
To maintain focus while making adjustments in the slot position, reinforce in your mind whether a pitch is a strike or ball before making your verbal call. The slight delay helps with call accuracy. Slow down!
Try to adjust upward and over, then mentally review strike zone again
Do the best you can to see the pitch and the plate