Adelaide chief executive Steven Trigg says the Crows are "bitterly disappointed" at the prospect of missing out on the hottest property at this year's NAB AFL draft, Bryce Gibbs, after it failed in its bid to have the 17-year-old eligible under the father/son rule.

The Crows put in a submission to ensure Gibbs - whose father Ross played 253 games for Glenelg - was eligible under the father/son rule, but despite the AFL announcing changes to the rule on Tuesday the star midfielder remains ineligible to be claimed under the rule by Adelaide and will instead go into the general draft pool come November.

That means that Gibbs, who was being tipped to be taken in the top five selections this year if not number one, can now be drafted by any club.

Under the previous father/son rule Gibbs was not eligible to be claimed by Adelaide as his father only played 191 games in Adelaide's 20-year eligibility period for father and son selections - which were the years 1970-90 immediately before the club was formed.

The Crows wanted the period to also include the club's formative years in the competition, which would have made Gibbs eligible as his father would have then played the 200 games required.

However, while the AFL announced on Tuesday it had ended the 20 year qualifying period relating to eligibility for father and son selections for the Western Australian and South Australian based AFL clubs, it rejected the Crows' bid to include the club's formative years in the qualifying period.

Only the sons of players who reached the qualifying mark before the WA and SA clubs entered the competition will be eligible to be claimed under the father/son rule, meaning the Crows still miss out on Gibbs, as he only played 191 of his 253 games with Glenelg before Adelaide joined the competition in 1991.

AFL chief executive Andrew Demetriou said the league adopted the change so as to ensure eligibility rules matched those of the other AFL clubs.

Demetriou said the father/son player qualification limits for West Coast (which draws on Claremont, East Perth, West Perth and Subiaco from the WAFL ) and Fremantle (which draws on South Fremantle, East Fremantle, Perth and Swan Districts) would remain at 150 WAFL premiership games while the qualification limits were higher for the SA-based clubs at 200 premiership games to match the size of the player pools from the greater number of SANFL clubs for Adelaide (drawing on Norwood, Glenelg, Sturt and South Adelaide) and Port Adelaide (drawing on Port Magpies, Woodville, North Adelaide, Central Districts, West Adelaide and West Torrens).

The Victorian-based clubs will continue to draw on their former player base only with their qualification to remain at 100 games, along with 100 games for the Brisbane Lions and Sydney (drawing on Fitzroy and South Melbourne players respectively).

However Trigg said the rule change still disadvantaged Adelaide.

"We have never had a father/son selection and we are not likely to now in the near future," he said.

Trigg said the Crows' bid to have the rule changed was not just about snaring Gibbs but about ensuring the club had the same amount of potential father/son selections as other clubs.

However he said by restricting the eligibility period to only in the years before the Crows' joined the competition meant most of those fathers whose sons would be eligible to play for the Crows under the new rule would now be too old to produce players of 17, 18 years of age.

"In a practical sense there is no greater chance for us to participate (in the father/son rule) than there was before," Trigg said.

However Demetriou insisted the new rule was fair to all clubs.

"The restriction of a 20-year period for WA and SA reduced the number of players for those clubs to draw on, and also excluded players who had qualified at an earlier time," he said.

"The removal of the 20-year qualification period prior to the entry of the WA and SA based clubs now brings a greater parity to the numbers of players that clubs can reasonably expect to draw a father/son selection.

Had Gibbs been eligible under the father/son rule, the Crows would have had the luxury of only using a third round draft pick to snare the star midfielder - who will now almost certainly go in the first round.

Gibbs recently captained Australia against Ireland in the first Test in the Under-17 International Rules Series and said he wasn't concerned about which club he would wind up at next year as Adelaide desperately sought to secure him under the father/son rule.

"Personally I don't really take much notice to it all. I just concentrate each week on playing for Glenelg and getting a kick out there," he said last week.

"If that happens, hopefully then everything else will take care of itself."

While Gibbs admitted he would be happy to be selected by any of the 16 clubs when the time comes, he said he would prefer to stay in Adelaide - which now appears unlikely.

"It would be great to stay in Adelaide with family and friends but my dream is to play AFL footy and I'll venture anywhere to fulfil my dream," he said.