Scott was uncharacteristically wayward off the tee in relatively calm conditions on Saturday, spraying at least six drives well to the right.
The reigning US Masters champion was still good enough to scramble to a four-under 68 to build a four-shot cushion over McIlroy who, himself, is a further four shots clear of third place.
But Scott, who is looking to become the second man behind Robert Allenby to claim Australia's Triple Crown (Australian PGA, Australian Masters and Australian Open) in the same season, admits he'll need to be better in the final round.
"I think for tomorrow to go smoothly I'm going to have to take some of the pressure off - chipping out and punching out from under trees is not how you win golf tournaments on the Sunday," Scott said.
"You need to be pretty solid and make it as easy as possible, so if I can get the driver sorted a little before tomorrow then I'll feel pretty comfortable going to the first tee."
"I've got a phenomenon (McIlroy) behind me playing as well, so I'm sure he's going to throw plenty at me tomorrow.
"It's going to be an exciting day. I'm going to have to do a couple of things better than I did today I think but as long as the eye stays in with the putter I think I should be able to hang on."
Scott added of the chance to cap a breakout season by claiming the Triple Crown: "It's an exciting position to be in with obviously a great chance to win my national championship tomorrow and then also to win the three events down here, which is an unbelievable spot to be in.
"If you'd told me a month ago, I wouldn't have believed you and I'm one round away but a lot can happen.
"Before this month started I hadn't won two tournaments in a row, ever, so there were no facts to back up that it would be a certainty that I would be sitting here in this position.
"To have this opportunity is a bit unreal ... and to finish it off tomorrow would be an incredible way to end the year."
Adam Scott wary of McIlroy on his tail
