RETIRED Brisbane Lions defender Matt Maguire admits he is torn on how far the AFL should go in protecting players from concussion.

Maguire announced his retirement on Tuesday after being unable to shake off the after-effects of a concussion sustained in a NEAFL game on Anzac Day.

Maguire Announces Retirement

Doctors found Maguire had blood spots on his brain, and the 31-year-old said he was unable to train at any intensity because of the injury.

His retirement comes in the same week as Carlton's Bryce Gibbs was suspended for a sling tackle that knocked out Port Adelaide's Robbie Gray last weekend.

Gibbs was banned for two weeks amid calls for the AFL to outlaw the tackle technique, in which an opponent's arms are pinned to their side and thus unable to protect their head.

A physical player who experienced both sides of the concussion debate, Maguire said on Wednesday the AFL and the tribunal have to be careful the spirit of the game is not compromised by the push to eradicate head knocks.

"I am still in two minds," Maguire said.

"I feel like Bryce Gibbs was playing the game in a manner that he's been taught to.

"I think concussion is a by-product of a contact sport.

"I am in favour of doing everything we can do to reduce the occurrences of concussions and head-high hits because it is a problem.

"But there's a fine line between ruling it out completely and also trying to keep the aggression and all the things that make our game great."

The game is seemingly split on the Gibbs tackle.

His Carlton teammates have vowed to keep tackling the same way, but Port Adelaide star Chad Wingard described it as a "great tackle" and Gray as simply "unlucky".

Footy doctor Peter Larkins has called for the AFL to legislate against the sling tackle, while North Melbourne great Wayne Carey tweeted that the game risks becoming "ring a ring a Rosie" if any rules are changed.

Maguire said his most recent experience with concussion has given himself a more "rounded" view.

"It's just given me more awareness on the effects of concussion," he said.

"I was very fortunate to have a long career, and even though I've suffered a lot of concussions, it's taken this one to actually make me aware of the full range of problems and issues associated with it.

"It's only on reflection that you realise how much it can affect you."

Maguire has been told by doctors he will make a full recovery, but said he had little choice to retire after blurred vision, head and neck pain, headaches and dizziness repeatedly foiled his attempts to train.