Several clubs have told Fairfax Media that the 2009 agreement where clubs were not to attend closed training sessions of rival teams has been broken too often, prompting it to be a discussion point last month at a meeting of the AFL Coaches Association's advisory group.

Port Adelaide coach Ken Hinkley recently was forced to evict a pesky Fremantle spy, Richmond has had its issues at Punt Road, another club was forced to turf out a spy twice in as many weeks, while one scout even emailed a rival club asking if it would mind if he attended a closed session. The answer was an emphatic "no".

AFLCA chief Mark Brayshaw said the agreement was on the verge of collapse.

"The informal arrangement between coaches is such that opposition analysts are not welcome at closed sessions which are publicised on the website," he said.

"However, there is a widespread view that even the informal arrangement is unworkable and the coaches' view on this is divided.

"Some of them think it should be abandoned, while others are prepared to give it one more go."

The 2009 agreement also included a spy agreeing to leave - and not returning - once spotted.

"It's not so much if you are seen to leave - if the training session is published as closed on the website, you shouldn't attend in the first place," Brayshaw said.

Officials from clubs unable to close their venues to the public have expressed they are at a disadvantage. Of the Victorian teams, only Carlton and Geelong can close their home venues. Melbourne, St Kilda, North Melbourne and the Western Bulldogs find it particularly hard to stage closed sessions.

While clubs do change their training times at the last minute to avoid prying eyes, it often doesn't take long for rival clubs to find this out.

Brayshaw said introducing penalties, such as a fine, had not been considered.

If the agreement is scuttled, Brayshaw said it would be a "free for all".

"Clubs would deal with unwanted guests in a manner they would determine is appropriate," he said.

"In some cases, coaches can't be bothered, and are quite relaxed. Others have said they are more concerned and would take steps to ask the opposition analyst to leave. It really is an individual position."

The issue was discussed last month by an AFLCA advisory sub-committee comprising Don Pyke (West Coast), David Noble (Adelaide), Mark Williams (Richmond), Brett Montgomery (Western Bulldogs), Chris Fagan (Hawthorn), Robert Wiley (Carlton), Alan McConnell (GWS) and Matthew Primus (Gold Coast).

The initial agreement was struck after then Melbourne scout David Dunbar angered Hawthorn coach Alastair Clarkson. A Melbourne spy was also caught after dressing as a construction worker when Waverley Park was under development.