What is the three seconds rule for defenders?

A defender must not remain in the 11 m Fan for more than three seconds unless they are marking an opponent within a crosse length (approximately 1.5 m).

• Only one defender may mark the same opponent without the ball in the 11 m Fan.
• A defender is "inside" the Fan only when both feet are fully in it; once one foot is on the Fan line or beyond, they are "out" and no longer eligible for a three seconds call.
• The rule takes effect when the team in possession crosses the ball over the restraining line into its attacking end.
• A defender marking an unmarked opponent standing directly behind the goal-circle is exempt from three seconds, but not from the shooting space rule.
• It is a major foul. Outside the AFA the free position is at the spot of the ball, with the nearest player from the offending team moving 4 m behind.