With regard to a “force” play, it seems to me there are a few ways for an umpire to make an accurate call. One could watch the runner’s foot hit the base and listen to the ball hitting the glove of the player covering the base. Or, just the opposite, watch the ball hitting the glove and listen for the runner’s foot hitting the base. Or, if even possible, try to watch both the ball/glove and the door/base at the same time.
Is there an accepted/best way to make the call?
For the most common type of force play, throwing the runner out at first, you are generally trained to watch the foot and listen for the sound. This will generally help in the case of most close plays. (Most plays aren’t at all close.)
This isn’t a foolproof method, as the ball does not always make a lot of noise when caught. This is especially true with other force plays - for instance, if the shortstop flips the ball to second to force a runner there it might not make much of a sound at all. You need to keep your eyes open and try to catch both events within your field of vision.
Yesterday there was an overturned play in the Cards-Pirates game, in which the pitcher covered first and took an underhanded soft-toss, which made no sound impacting the glove. But making the call audibly like that is standard procedure for MLB umpires. They admitk and eveeryone agrees, that is ithe most reliable way to make the call. The base and the ball are six feet apart, and cannot both be within central focus for the ump.
They got caught doing that way back in the 50’s,when Dodger first-baseman Gil Hodges slapped his mitt with the throw half way across the infield, and the Ump called Whitey Ford out at first in the World Series. A cameraman (they were still allowed on the field) got a perfect shot of the bad call, and the umps got busted.