Defending champion Rory McIlroy has endured a tough start to his final round at the Australian Open in Sydney.

Starting the day six shots off the leaders at one-over-par, McIlroy was in need of birdies but found trouble at the par-5 fifth, the hole from which most expected the world No.1 to mount his challenge.

But exactly 24 years after Greg Norman’s famous albatross on the hole in the 1990 Australian Open, McIlroy hooked a three wood into the trees en route to a nasty bogey six.

McIlroy needed several clutch par putts on the front nine to keep his title hopes flickering at two over for the tournament, seven strokes adrift of the leaders.

Crowd favourite Adam Scott birdied the first hole to join Greg Chalmers, Brett Rumford and American Jordan Spieth on top of the leaderboard at five under.

Spieth disagreed with Rumford after Saturday’s third round that the course was bordering on unplayable entering Sunday’s climax.

Rumford claimed the Jack Nicklaus-designed layout at The Australian was “on a razor’s edge” following an overhaul four years ago.

Only eight players – headed by Spieth, Rumford and Chalmers – were in red figures entering the final round.

“They are trying to create a golf course that’s as unplayable as they can get it without it being so and it’s right on that point,” Rumford said.

Spieth, Masters runner-up at Augusta this year to Bubba Watson, had no complaints, saying the course was set up beautifully for a national championship.

“I certainly don’t mind it all,” the 21-year-old said on his first visit to Australia.

“I almost prefer it – wind and a very difficult golf course, I feel like plays into my hands.”