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Judging Guide
Jan 29, 2026

Jumped Straight Up but Called a Foul? 'Cylinder' & 'Verticality'

"I just jumped straight up!" We've all been there. Understanding what referees look for in 'Cylinder' and 'Verticality' will save you from unfair calls.


1. Your Space: The 'Cylinder Rule'

Every player has a virtual cylinder of space on the court.

  • Up: Infinite space from the floor to the ceiling
  • Front: Up to the palms of the hands
  • Sides/Back: Defined by the body's frame

If you jump vertically within this space and contact occurs, it's not a defensive foul. It might even be an offensive foul.

2. Verticality: Point A to Point A

Referees check: "Did they jump from A and land on A?"

✅ Legal

Jumping vertically with arms extended straight up. Contact is considered effective defense.

❌ Illegal

Jumping from A to B (into the attacker), or swiping arms forward/down.


3. Video Review Checkpoints

In slow motion, referees look for: 1. Did the defender's feet leave the floor before the attacker entered their space? 2. Did the body lean mid-air? 3. Did arms break the vertical plane?

Maintaining verticality is often better defense than chasing a highlight block.