'THIRD MAN up' has been banned in a radical change to the laws of the game in 2017.

In a surprise move, the AFL notified clubs on Wednesday that next season only nominated ruckmen will be able to compete at a contest for a throw-in or ball-up.

Other players will therefore no longer be permitted to contest a ruck contest as 'third man up'.

A stricter interpretation of deliberate rushed behinds will also be introduced and the interpretation of where a player draws high contact will be simplified. 

However, theto ban 'third man up' decision is sure to spark debate, with coaches split as to whether a rule was necessary when consulted on the proposed change at the annual AFL laws summit on the day of the NAB AFL Draft. 

The AFL Commission approved the contentious recommendation from the League's football department that came after widespread consultation with a range of relevant stakeholders.

The AFL is understood to have been concerned that if it continued to allow players the ability to go 'third man up' the role of the ruckman would be under threat.

AFL football operations manager Mark Evans said it was important a change was made to protect one of the game's unique features.

"Eliminating the 'third man up' at ruck contests will support the recruitment of tall players and ensure our game continues to be played at the elite level by players of various sizes and differing abilities," Evans said.

The incidence of players going 'third man up' at stoppages has increased dramatically in the past two years from 8.5 per cent in 2014 to 13.2 per cent last season.

Statistics show there is no link between the controversial tactic and clearances, and medical advice was that injuries had not increased because of the spike.

However the umpires believe banning 'third man up' will make the game easier to adjudicate.

Many in the industry are split, with Brownlow medallist Patrick Dangerfield saying a fortnight ago he did not think there was a need to ban it.

However, Brisbane Lions ruckman told AFL.com.au that from a selfish point of view as a ruckman, he would like the see the rule changed.

"I don't reckon I have been injured from being jumped into, but I like the contest and hate it when you think you have got a bloke covered and someone comes out from behind," Martin said.

"It would help it be a pure battle of strength, otherwise we just get another midfielder because they are reducing stoppages anyway."

Lions coach Chris Fagan was less certain a change was needed when he spoke to SEN 1116 last Friday.

"Keep it, but if you're good enough, legally block the third jumper," Fagan said.

"If the third jumper [is] good enough to beat the blocks around the stoppage, then so be it."

Umpires have been briefing clubs on the proposed changes with the high tackle also being looked at.

"Umpires will be instructed that whether a tackle is reasonable should always be their first assessment when adjudicating high contact," Evans said.

Umpires will be asked to call play on when a tackle is assessed as reasonable and the player with the ball is responsible for the high contact however the call carrier will be protected against high or reckless tackling.

The stricter interpretation of the deliberate rushed behind, will take into account the distance a player is from the goals and whether the defender had a chance to dispose of the ball.

Evans has indicated that players who have clear possession will be expected to keep the ball in play under the new interpretation.

The protected area around the mark will also be clarified, with the umpires looking at enforcing the area once the player in possession has moved back on their mark.