COACHES have reverted to a defensive mindset halfway through the season and AFL football operations manager Mark Evans wants to know why.

After a mid-season review revealed the game had opened up and coaches were embracing more attacking game styles, high stoppage numbers and congestion have re-emerged as an issue.  

There has been an average of 74 stoppages a game this season, the highest since 2004, and round 15 saw a season-high average of 84 throw-ins or ball-ups.

Evans said there was an element of scaremongering in the recent concerns about the congested nature of games, but he was curious as to why coaches had stopped orchestrating attacking games styles. 

"I think what we've seen over the past six or seven weeks is a rise in stoppages and a rise in boundary line play where I think coaches have become a little bit more afraid of directing the traffic inboard," Evans told 3AW.

"The question for me in talking to some of these coaches is when you took [the game] on and you saw you were actually kicking more goals out of that, but you were possibly giving up some more goals, why have you now constricted?

"Why are we now going more towards the boundary line?" 

Evans said the AFL had seen attacking play earlier in the season partly because of the stricter interpretation on holding the ball, but positive coaches had played a bigger role in that early shift. 

He said the game couldn't necessarily just wait for the next evolution, with fewer players on the ground, restrictions on where players can stand at stoppages and umpiring changes all floated as suggestions.  

"Is it on our agenda to try and reduce stoppages and to try and spread play out? Yes it is," he said.

"What are the levers we can pull? Interchange cap has been thrown up as one of those … it might be a combination of everything."

Evans was keen to highlight there had been "spectacular" football played in the earlier rounds this season and matches had been gripping, despite scoring not increasing.

He stressed he was not a supporter of zones, but there was room for a debate on adjudicating where players could start at stoppages.