The AFL has moved to close a loophole in its contentious protected area rule, saying there had been "unexpected exploitation" by players.
Umpires have been told to no longer pay 50m penalties when players deliberately run their opponents into the protected area with the intention of creating a split between them.
The rule permits a defending player to follow their opponent into the protected area around a player taking a set kick, provided they are within two metres of each other.
Where a split happens, and the defender continues to run through and clears the area, the umpires will no longer pay a 50m penalty.
Some players have run around the man on the mark to create the split and expose their opponent to a potential 50m penalty.
The AFL called the tactic an unintended exploitation of the rule in a statement released on Tuesday.
"The protected area rule is designed for the kicker to have options to move the ball," said umpires boss Dan Richardson.
"It is having the desired effect, however there have been more and more instances of players deliberately running their opponent into the zone with the intention of getting split and/or drawing a 50m penalty.
"If this 'split' of players happens, providing the defender moves to vacate the area, the umpires have been instructed to no longer apply a 50m penalty.
