Adam Scott is perched on the edge of history. But Rory McIlroy could play the spoiler.
Taking a four-stroke lead into Sunday's final round at the Australian Open, Scott can become only the second golfer to win his country's triple crown of major tournaments.
"It's an exciting position to be in," he told reporters. "Obviously a great chance to win my national championship tomorrow and then also win the three events down here which is an unbelievable spot to be in."
McIlroy stands four strokes behind in second. He is simply looking to win his first event of 2013, hoping to put a happy ending on a sad season.
On Saturday, the golfer from Northern Ireland shot a two-under 70 marked by a costly double-bogey.
"I feel like I left a couple out there on the back nine," he said. "Obviously got a tough job on my hands to try and catch Adam."
Scott, who shot a four-under 68, could match Robert Allenby's 2005 feat, winning the Open, the Australian Masters and the Australian PGA.
"One round away," he said. "But a lot can happen."