2014 NAB Challenge rules:The nine-point 'supergoal', a feature of the pre-season competition in recent years, will again be in play.
The introduction of the interchange cap limit will provide an added point of interest during the NAB Challenge as clubs come to grips with restrictions on bench moves.
Rotations for the NAB Challenge will be set at 130, dropping to 120 for the home and away season. There will be no restriction on the number of interchanges per quarter during the pre-season.
Teams will be permitted to field squads of 26 players per game, with eight players on the interchange bench (two of them being substitutes).
Coaches will be allowed to 'reset' their substitutes at half-time.
The AFL announced rule changes relating to body contact at the end of last year, with these to be in place during the NAB Challenge.
For example, "a player electing to bump will be cited for rough conduct if contact comes via a head clash". Players will be instructed that a head clash should be reasonably foreseen when bumping.
Contact with the legs has also been addressed, with a free kick to be paid if a player makes forceful contact below the knees or acts in a manner likely to cause injury, even if contact
does not occur. Also, changes have been made to discourage players from seeking to draw forceful high contact.
http://www.afl.com.au/news/2014-02-08/nab-challenge-explained