AFL chief executive Gillon McLachlan confirmed the discreet cameras installed inside the goalposts at the MCG, which mirror racing's photo-finish system of showing exactly when the line is crossed, would be used at every other finals venue, too.

Also, the customary rostering of one official per match to adjudicate on score reviews will be doubled, with a second official to oversee proceedings and intervene in case of a mistake in reviewing the footage.

McLachlan admitted the current system was not perfect, but that it was not practical to achieve that throughout the season.

"The whole goal review [process] is really problematic ... we've got four goalposts, this whole series of [variables] which might impact the score, [and because of that] we would have to spend so much money to cater for everything," the league's boss told 7Mate's Talking Footy.

He said of the 21 goal-umpiring decisions overruled this season, 18 had been rightly corrected. In regard to the three decisions incorrectly changed - such as when Adelaide's Rory Sloane had a goal withdrawn in round 21 - he said his preference was for the score review staff to defer to goal umpires unless there was conclusive evidence a mistake had been made.

Despite such glitches, McLachlan was adamant the system as a whole was preferable to instances of a clear blunder - such as in the 2009 when Geelong's Tom Hawkins was incorrectly awarded a goal for a shot that hit the post - going unnoticed, especially in a final.

"Some people have said, 'Get rid of it altogether', but I think you've got to correct the obvious ones," he said. "If we're not correcting those - and I think that had a bearing on the way that grand final went - I think that would be a regressive step."