AUSTRALIAN rules is mocked internationally as ''no rules''. Locally, followers despair of too many rules, or at least too many interpretations, and too many different emphases. They further despair that those interpretations appear to change from week to week.

The now infamous tweets sent out by two Carlton players last Thursday night centred on the apparent sanction on the player who makes the mistake of gathering the ball. It is not unusual now for two or more opponents to tackle him, and for other players from both sides to pile in, forming a scrum.

The AFL, with its premium on free flow, loathes this. The umpires are under instructions to avoid ball-ups, either by waiting for the ball to shake free, or to penalise the player at the bottom of the heap. It puts them in an invidious position.

The most controversial example was a free kick paid against Aaron Joseph, directly in front of the West Coast goal. When the whistle went, there were three Eagles and two Blues stacked on top of Joseph, and he did not even have the ball.

At the risk of adding to the clutter of rules and interpretations, there is another way. Years ago, ice hockey introduced the ''third man in'' rule to mitigate fighting. The original adversaries may or may not be punished, since it is not always possible to establish guilt. But the next man in is penalised, since he plainly has no business there.

Here, the issue is not fighting, but unsightliness. A form of ''third man in'' might work. It would apply against a player who hurls himself into a pack, either to make it impossible for the player on the bottom to release the ball, or to give the umpire to believe that the only way out is a ball-up, but in any case serving only to make the pack bigger.

It is incongruous that a player can be penalised for diving on the ball - you can hear the umpire say so in the Joseph case - but not for diving on other players.

This rule would still require considerable umpires' discretion. Frequently, three or more players throw themselves in, with only the purest motive, either to take the ball or tackle the taker. They must not be discouraged. But sometimes, the extra men are just that, extras, with no intention other than to silt up play. They should be deterred.

''Third man in'' would not be a panacea. In hockey, fighting still is endemic. Nor would it necessarily please fans. In the Joseph incident, the second man was Jack Darling, who ended up sitting on top of Joseph, quite plainly trying to trap the ball between them.

But the third man in was Carlton's Michael Jamison, who not only rode into Darling's back, but in the rough-and-tumble ended up with the ball in his hands.

Under ''third man in'', it would have been a free kick to West Coast in front of goals anyway.