3-Man Mechanics and Basic Principles

Communicate with each other: visually and verbally
Go out on all trouble fly balls: OF converging, OF hard in/out, fair/foul, HR/2B possibility. NEVER cross the dirt/grass line if in the middle.
If an umpire goes out on a fly ball, revert to the 2-man system
Only rotate on BATTED balls hit to the OF with no runners on, R1 only, or R1/R2 tag up situations
Check swings: U1 has RH batters always, U3 has LH batters always
With 2 outs, U1 will go back to A and U3 will come into the middle (if nec)

U1 has fly balls hit from CF to his left over to RF
U3 has CF straight in/back and to his right over to LF
Watch each other on all fly balls to avoid 2 umpires going out on the same fly ball
If both umpires go out by accident, HP needs to be aware and get trail the runner for a possible play at 2B!

If on the line, you have the OF toward the line
If in the middle, you have the V (LF player to RF player)
HP has LF towards the line and RF towards the line depending on positioning of your partners

With no runners on base, follow the umpire that goes out. That means if U1 goes out, trail the BR up the 1B line and have plays on BR back into 1B. If U3 goes out, go in the direction of the ball and help on catch/no catch for U3. If no one goes out, rotation is on and you have plays on BR at 3B.
With runners in scoring position, you WILL NOT ROTATE to 3B unless you have a R1/R2 tag up situation. o You still rotate to 3B with R1 only on batted balls to the outfield
Pre-pitch communicate with your partners after each batter, take the lead to make sure the entire crew understands the situation.

Initial positioning:	No runners on base, same as 2-man. With R1, get closer to 1B so you can see any pickoff attempt. When in the middle, stay deep B. With 2 outs, be in A.
No runners on:	Fly ball responsibility from CF to his left all the way to RF. Read U3 on fly balls to CF over to LF. If U3 goes out, come in and pivot and take responsibility for BR. On base hits or U3 not going out, walk towards 1B and watch BR touch 1st. Rotate home if BR commits to 3B.
R1:	Fly ball responsibility from RF towards the line. On base hits, rotate to home plate once R1 commits to 3B
R2 or R2/R3:	Initial position is deep B. Fly ball coverage within the V. All calls at 1B and 2B. If U3 goes out, then calls at all bases.
R1/R2, R1/R3, Base Loaded	Fly ball coverage for RF towards the line. On base hits, come in and pivot taking responsibility for BR at 1B or 2B.

Initial Positioning:	With no runners on, treat 3B as if it was 1B (stay behind the third baseman just like he was the first baseman). With R3 or R2/R3, get closer to 3B for possible pickoff plays. With R1 only, be in deep B or deep C. With $1/R2 or bases loaded, be in normal C. Remember, with 2 outs U1 will go back to A so you may have to go into the middle depending on the situation.
No runners on:	Go out on trouble fly balls in your coverage area. Otherwise, come in towards 2B for possible plays on BR.
R1:	Be in deep B or deep C. Fly ball coverage in the V. On base hits, rotation is on! Take responsibility for calls at 2B on R1 and all calls on BR at 1B or 2B. If ball stays in the IF, all calls on R1 at 2B or 3B.
R2 or R2/R3:	Be in modified D position. Go out on trouble fly balls in your coverage area. On base hits, stay at 3B and watch for base touches. With 2 outs, get into the middle and have all calls at 2B and 3B.
R3:	Be in modified D position. Go out on trouble fly balls in your coverage area. On base hits, make sure R3 commits home and come into the middle for plays at 2B. With less than 2 outs, take tag ups of R3 at 3B whenever possible.
R1/R2, R1/R3, Bases Loaded:	Be in C position. Fly ball coverage within the V. On base hits, take all responsibility for calls on R1, R2, an R3 at 2B or 3B. U1 will take responsibility for BR at 1B or 2B.

3 MAN MECHANICS And Basic Principles