SIX POINTS for a goal; one point for a behind.

Since the creation of the Victorian Football League in 1897, the scoring system for the premiership season has not changed one bit.

And according to the 18 AFL senior coaches, it must always be so.

As part of the exclusive survey carried out by AFL Media and the AFL Coaches' Association, the coaches were asked to name three aspects of the game that must remain sacrosanct.

The scoring system came out first, followed by having 18 players from each side on the field at all times.

This is particularly timely given recent discussion that one way of dealing with on-field congestion is to reduce the number of players on the ground, with calls for 16 players per side to be trialed during next year's NAB Cup.

The coaches were also strong on ensuring that there be no zones or restrictions on where players can run on the ground.

Other aspects of the game that more than one coach nominated to be preserved included the shape of the ball, protecting ball players, the preservation of physical contact and the centre bounce.

The father-son rule, an 18-team competition, the draft, the salary cap and four players in the centre square were also among the elements of the game regarded by coaches as sacrosanct.

Get your copy of this week's AFL Record to see how the coaches responded to every question in the 2012 AFL Media/AFLCA Coaches Survey

?You can follow AFL Media senior writer Ashley Browne on Twitter @afl_hashbrowne