Andrew Demetriou is confident the league's player rules would stand up in court.

Andrew Demetriou is confident the league's player rules would stand up in court. Photo: Pat Scala

KURT Tippett came close to taking the AFL to court after his management learnt several days ago that the league would block any trade involving the out-of-contract 25-year-old.

The Saturday Age understands Tippett's father Tony looked at an injunction that would have challenged the AFL's player rules in a bid to get his son to Sydney, but that the player decided against it.

Facing deregistration for signing a contract with the knowledge there was a second irregular agreement, Tippett has become increasingly concerned about his playing future.

Tippett's lawyer, David Galbally, has written to the club claiming the letter it induced Tippett to agree to was ''misleading and deceptive'' and in breach of the Trade Practices Act.

Tippett and Sydney were told four days ago he could not be traded, with AFL football boss Adrian Anderson sending a copy of his explosive secret agreement with Adelaide to Swans chief Andrew Ireland in a bid to demonstrate the serious nature of the investigation.

AFL boss Andrew Demetriou said yesterday he was not aware of any legal threat but told The Saturday Age he was confident the league's player rules would stand up in court. ''I'm very confident about our rules,'' said Demetriou. ''I understand it's a restraint but I also understand our rules are legally sound.''

Galbally was not available for comment although he is understood to have been present when the forward, who remains with his family on the Gold Coast, was interviewed by the AFL investigator early this week.

The AFL's investigators, Brett Clothier and Ken Wood, have also spoken to Tippett's father and are expected to interview both men again.

The gap between Adelaide and the player who booted four goals for the Crows in his final performance for the club has continued to widen.

The Crows remained on the defensive yesterday, with beleaguered chief executive Steven Trigg forwarding a letter to members asking them for support ''in such difficult times as these''.

As the league's auditors moved in on Adelaide's AAMI Stadium offices and despite the fact of a hidden three-year agreement, Trigg wrote: ''Our intent throughout was to comply fully with all AFL rules in the manner and process of our drafting, trading and player payments.''

Trigg's former football lieutenant John Reid, who signed the contentious agreement, which appeared under the Adelaide Football Club's letterhead, has also continued to claim he has broken no rules.

While conceding the Crows ''sold our soul'' in signing Tippett at the end of 2009 to such an exorbitant and contentious deal, Reid has always claimed the secret part of the deal was instigated by Tony Tippett and player manager Peter Blucher.

That claim has not been helped by the evidence of the letter revealed by The Age three days ago. While Blucher faces deregistration for agreeing to the side deal on behalf of his client, there seems little doubt Reid, in the knowledge of Trigg, put forward the offer.

The Crows will claim they attempted to fix the deal once they realised it may have contravened AFL draft rules.

They will also claim the Tippett team used the letter as a threatening device.