Three-Person Mechanics Guidelines

By Dennis Morris

Basic Responsibilities of the Lead

Stay in your primary

  • Be square to baseline and facing your primary

Find a reason to rotate (we want more rotations; not fewer)

  • L does not rotate enough
  • If ball rotates over and post players rotate over and L does not rotate, there is too
    much for C to watch
  • Having two officials on strong side increases chances of off-ball fouls being
    called, especially rough play fouls

Work the baseline

  • Start wide and close down as ball comes to middle of court
  • Never officiate in the paint; only use during rotations
  • Stay back 1-2 feet from baseline if it gives you a better angle (angles should dictate your positioning–should be 90 degrees between players, not straightlined)

Close down and prepare to rotate

  • Must close down before rotating

Use of drop step

  • If you are too late in rotating and there is a drive to the basket from the other side of lane, L should drop off the baseline (from the closed-down position) to get a better angle

Stay away from calling goaltending and basket interference

Three point signals

  • Only time you signal is on a fast break and leave hand up until T picks it up; don’t ever signal it is good

Basic Responsibilities of the Center

Must be active and have a good game

  • Stay in your primary – you have enough area to officiate without having to go into your partners’ areas
  • Stay straight up to court; only position that does this

Dictates rotations on traps

  • You initiate rotations 1% of the time (L must rotate over if you initiate it)
  • This must be a trap, not just a dribbler on your side

Ready to assist on out of bounds play

  • Help on out of bounds calls on end line on your side of court if L needs help (get
    eye contact before signaling)

Basic Responsibilities of the Trail

Angle-in from the 28′ line

Do not release the dribbler until the Center picks it up

  • Center must usually pick up ball before T releases it, otherwise the ball could be watched by no one!
  • T and C must continue all counts if they initiate them

Two Trails are not good

  • C should not be quick to move to T position; you usually have a great angle if
    you don’t move

Trail the play in pressing situations

  • Always trail the play
  • C must be ahead of the play but don’t be too quick to turn around and leave
  • C follows the crowd down the floor
  • C must call fouls and block/charges if the dribbler quickly moves up court and T is trailing too far behind

Rotation Overview

Movement of Lead

  • When your post player goes over, you will rotate 95% of the time
  • As L rotates, T will step down immediately to C (on a string with L)

Two Centers are okay

  • Old C stays momentarily

Avoid being in a big hurry

  • Only go to T when you need to (you usually have a better angle as a C); you can even officiate in C position and go straight to the new L position on a change of possession
  • L boxes in play

Guidelines When Working the Lead Position

Start wide

  • Start between lane and 3 point line (never go out past three point line)
  • Always watch primary but know where the ball is at all times through your peripheral vision

Don’t be afraid to rotate

  • Never rotate on a shot, drive, or rebound in progress; go back if you are in process of rotating and these three items occur
  • When you rotate, watch the post players, don’t look at the outside players, the new T has them

Close down

  • Always make rotations from the lane line
  • On rebounds, move out wide for better angles, you cannot see fouls if you are closed-down

Ball settles below the free throw line

  • Immediately rotate if you haven’t done so already

Study the game

  • Follow the post players

Look for the first competitive match-up

  • As you come across, look for your first competitive match-up (closest pair of post players)
  • New C’s first competitive match-up is the L’s old primary and off ball

Always stay in your primary

  • Don’t make calls around the free throw line on jump shots or collisions; you are too far out and you are guessing; the C has the best inside-out look
  • On drives down your baseline, don’t close down because it will give you a bad angle

Your depth off the baseline depends on getting the best angle

  • On rebounds this will be close to the baseline and wide; on post-play you’ll probably want to be deeper off the baseline to get a better angle

Guidelines When Working the Center Position

  • Don’t rush out at the C position on rotations (stay put)
  • Watch post-play and curl plays that are off-ball; if you have the best angle you can even go across to the other side of lane
  • Step down on shots and watch rebounds (get inside-out look between players to see displacement)
  • Only initiate a rotation on a trap, not just because a dribbler is on your side; the L should initiate these

Guidelines When Working the Trail Position

  • Stay at 28 foot line
  • Stay active and assist with post-play when the ball moves away from you
  • Watch travels on the post players in L’s primary
  • Watch goal tending and basket interference
  • Step down on shots and watch rebounding
  • Always know where the L is because you have to step down to C when he rotates to pick up the L’s old primary

Other Aspects

Double whistles

  • C and L: split lane line, C’s primary is on his side of lane
  • L and T: L is primary unless he picks up a drive late
  • T and C: whoever the play is going towards has primary whistle

Understanding where the play originates

  • You may take a play on a block/charge if it originates in your primary since your
    partner may pick it up late

Staying in your primary and trusting your partners

  • Never officiate more than 4 players, that means a rotation should occur or you are watching outside your primary
  • This is crucial for the C
  • The person with the best angle on a play (90 degrees or inside-out between opponents) should make a call; do not look through players’ backs and guess because one of your partners should have a better angle

Fast breaks


  • New L needs to look behind shoulder and beat play to spot between lane line and three point line (do not close down, you’ll have a bad angle on swipes away from you) so you are stopped and can accept a play
  • L should not cut across the court, the C must make block/charge calls on his side of lane or ones that are high (near FT line); the L is secondary on these calls
  • C must stay put on transitions; the more people in the back court, the deeper and longer you’ll stay. Also look for any cheap shots from emotions on the previous play (elbows in back, etc.); if you leave early, you and the new T will probably miss.
  • Follow the crowd and take foul calls sideline to sideline in the middle of the court,
    you have the best angle and the T will be straight-lined.