The Cats avoided sanction from the AFL over the secret arrangement struck in 2024, which was revealed on Thursday, with an undisclosed player.
The player signed an agreement taking on legal responsibility for future brain trauma in a bid to exonerate the club and its medical staff from court action down the line.
Calling it a "complex and unique case", the AFL insisted it was "satisfied that the letter was not used by Geelong to allow a medically unfit player to return to play".
Geelong also issued a statement, saying they would remove the waiver from the contract.
"The club was not attempting to vary the terms of the AFL standard playing contract, or attempting to avoid its responsibilities under health and safety laws," the Geelong statement read.
Fremantle veteran Mason Cox was unimpressed by the situation.
"It's very poor behaviour, to be honest with you," Cox told Nova 100 on Friday.Â
"As a player, health and safety of any job, of any kind of employer you would expect to be at the highest and to be trying to do backdoor deals without the AFL Players Association being involved is pretty poor."
Cox said players needed their support systems and legal representation - their agent and the AFLPA - involved to walk them through such a process.
New AFL Commission chair Craig Drummond was the president of the Geelong board when the deal was struck.
Drummond was not mentioned in the AFL statement.
Deciding not to front the media to explain the situation, Drummond issued a three-line statement on Thursday night calling concussion a "challenging medical and legal issue for all contact sports globally".
Former Hawthorn president Jeff Kennett lamented the concussion case.
"I am profoundly disappointed. It is totally inappropriate," Kennett told 3AW radio.
"The fact that Geelong now says 'we've ripped up the sort of agreement' is no good, and I hope Mr Drummond is totally transparent with the community."
Kennett demanded to know who signed off on the agreement.
"What sort of person would sit there and say 'we're going to take away the rights of a player who's had a number of instances where their own capacity to make that decision may be limited'?" he said.
"I just don't understand.
"I know at Hawthorn we have a doctor on the board - a physician. This would never have been allowed, even if some of the board members said, 'let's do it.' It's just inconceivable."
When asked about the bombshell revelation, Western Bulldogs coach Luke Beveridge spoke generally about concussion, rather than comment directly on the Cats' case.
"I think every player wants to keep playing until your boots fall off," Beveridge said after the Bulldogs' shock loss to North Melbourne.
"All I know that when I was playing, we all had concussions, and if I had to sign a waiver to keep playing, I would have."
Beveridge stressed clubs were careful with their players.
Kangaroos coach Alastair Clarkson, who earlier this year sprayed insurance company Zurich for rejecting concussion insurance claims, feigned ignorance and insisted he knew nothing about Geelong's case.
Multiple AFL players, including former Melbourne star Angus Brayshaw, champion West Coast defender Jeremy McGovern and former No.1 pick Paddy McCartin, were forced into retirement due to repeated concussions.
Several deceased players, including Danny Frawley, Shane Tuck and Graham 'Polly' Farmer, were posthumously diagnosed with degenerative brain disease Chronic Traumatic Encephalopathy (CTE).
There is also a multimillion-dollar concussion class action against the AFL, led by former Geelong defender Max Rooke, in the Supreme Court of Victoria that is set to go to trial next year.
