RICHMOND coach Terry Wallace has called for further changes to the AFL interchange system to allow emergency players and ensure a level playing field.

"From an interchange point-of-view, I don't think it should ever be 22 playing against 20," Wallace said.

"I would love the ability to have emergencies replace blokes who can't come back on, so that you've always got 22 playing 22.”

Talk throughout the season centred on the scenario of a team losing players to injury during the grand final and having to battle on with a reduced bench.

Hawthorn did exactly that, losing Trent Croad and Clinton Young prior to half-time, but won the match anyway.

Wallace said he was a fan of the system used in the old pre-interchange days, where a couple of emergencies were available if a player was unable to continue.

The AFL is considering introducing a similar system in the NAB Cup this year, in addition to having six players on the interchange bench.

Wallace said that removing any need for players to be injured before being replaced by an emergency could be the key to making the system work.

"If you just allow the emergencies to be there, and not having to be used for injury ... you don't have to worry about it being policed,” Wallace said.

"That way it's always 22 against 22. If you do it the other way, where you need medical certificates, etc, it could never work.

"What I don't like ... I would hate to get to a grand final and the grand final be the result of one side losing three blokes before half-time.

"But on the other side of it, I think the AFL is more looking towards – and it's their game, we're only putting up opinions – I think that they will be more looking towards getting evidence to restrict interchange rather than going the other direction and adding to interchange.

"So I think that's probably where they're heading."

In round six, the Sydney Swans were fined $50,000 for having 19 men on the field late in a match at Telstra Dome which they drew with North Melbourne.

The league changed the interchange system after that match, further formalising how players entered and left the field. And they found a supporter in Wallace who said that those alterations had, in hindsight, worked well.

"I think the changes they made to the interchange rules, once they got that sorted out, and there was a bit of common sense coming in, I think that that's been fine,” Wallace said.

"It was getting to the stage of being a tad ridiculous about blokes being able to just come on and off the ground wherever they wanted to, so I don't have any issue with that."