Millar finished the Australian Open well down the leaderboard in a tie for 55th after making too many errors in the second and third rounds at The Australian Golf Club in Sydney.

He stabilised on Sunday with a final round of even par, but his slide down the leaderboard hit his rankings and his hopes of playing at some of the world's richest events next year.

If Millar finishes in the top three of the Order of Merit, it could open the door to play in two of the four World Golf Championships events next year, carrying minimum prizemoney of around $US45,000 ($A62,555).

Millar is also in contention to win the Australasian player of the year at the inaugural Greg Norman Medal on Tuesday night before he plays in the Australian PGA championships.

"It's still a possibility to [to get a start at the World Golf Championships], but it's a bit of a longer shot now," Millar said.

"I'll need a top two or three at the PGA ... it maybe slipped away a little this week but you never know.

"I'm feeling pretty fatigued, but I'll just rest up and get right to see what happens."

Millar shot two birdies and two bogeys in his even-par round before flying to the Gold Coast on Sunday night.

He will play in the Holden Scramble final on Monday and then turn his attention to getting his groove back at the Royal Pines Resort.

The 39-year-old Gold Creek Country Club training professional had hoped to carry on with the form that saw him lead the Australian Masters two weeks ago.

But he struggled to find momentum in tough conditions in Sydney.

"I just couldn't make a putt [on Sunday]. I made a soft bogey at the sixth and I was thinking it was going to be one of those days. But I hit some good shots and couldn't make putts," Millar said.

"It just wasn't quite right this week. The putts weren't falling ... I've just got to recharge a little bit and then get back into it on Wednesday for the PGA. Spending a bit of time away from the course won't be a bad thing."