Brisbane captain Dayne Zorko gifted St Kilda's Jack Higgins a goal for an infraction on the mark and Lions coach Chris Fagan wants the AFL to tweak the rule.

Brisbane coach Chris Fagan has raised fresh concerns over the AFL's 'stand' rule, warning a grand final could be decided by a minor infraction by a player on the mark.

The 61-year-old's comments came after Lions captain Dayne Zorko gifted St Kilda's Jack Higgins a goal during Friday night's contest at Marvel Stadium.

Higgins faked a handpass to teammate Jarrod Lienert and Zorko flinched on the mark, taking one step to his left before realising he'd been tricked.

Higgins was awarded a 50-metre penalty and converted his set shot from the goal square, sparking a Saints fightback before Brisbane steadied to win by 15 points.

"Do we want a grand final decided on a decision like that? Can you imagine?" Fagan asked reporters post-match.

"I can't imagine that. My personal viewers is we should review that rule and that's not a criticism of the way that it is.

"I think it's been quite a good rule but I think a player on the mark should be allowed one step to the left or right as long as he doesn't go any further than that.

"I don't think that should be a 50-metre penalty. That's just my view."

Fagan's comments will spark further debate over the weekend and the Lions coach hopes the conversation will put pressure on the AFL to look at the rule before the finals.

"It's unnatural not to move when somebody does that," Fagan said.

"Players play for it and good on them - that's clever football - but you shouldn't get a 50-metre penalty for just moving slightly.

"Am I going to get in trouble for saying that? I hope not but I think we should talk about it."