Aaron Baddeley, who led the tournament after both the first and second rounds, faltered on Saturday with a 3-over 74. He shares seventh place at 6-under, four shots off the pace.
'It was a weird day today,' said the 19-year-old Australian. 'I tried not to get too frustrated and stayed focused. I still thought I was playing alright, I guess I missed it in the wrong spots today.'
Green, who began the day three shots behind Baddeley, had a mixed front nine on Saturday with three birdies and two bogeys. He birdied No. 1, but promptly gave the stroke back with a bogey at the par-4 2nd.
Back-to-back birdies at six and seven were negated by a bogey at the ninth. Green finished the front-nine with a 1-under 34.
Green steadied on the back side with birdies at 10 and 14. His birdie at 17 gave him a piece of the lead.
Green is in the middle of a spectacular run. Last Sunday, Green aced the par-3 12th and collected $500,000 (Australian) and a runner-up finish for his efforts.
'It's all been a bit of a blur,' said Green, referring to his fairy tale run. 'I don't feel like I'm playing any differently than I was four weeks ago. All in all I've just been driving the ball a bit better this week and I putted pretty well today.'
Lonard scattered two birdies and two bogeys over his front nine. He birdied 9, 13 and 14 to take the outright lead but dropped from the top with a bogey at No. 16. Lonard rejoined Green in first with his fifth birdie of the day at 17.
'It was a tough day for scoring, a tough day for hitting it close to the pins,' said Lonard, who posted a 3-under 69 on Saturday. 'When they put the pins in the corners it's not a real attacking course. For me in particular, it was probably a day of survival.'
Gardiner fired a 9-under 63 on Saturday to gain a share of second. He birdied the 12th after he chipped in from a greenside bunker and added two more at 17 and 18 for the lead at the time.
'That's what you have to do when you play early on Saturday,' said Gardiner. 'I'd probably prefer to play a bit later, but when you're shooting 63 you don't mind when you're playing.'
Painter carded a 3-under 68 on Saturday.
Geoff Ogilvy and David Smail share fifth place at minus-seven.
Baddeley heads a group of five golfers at 6-under. Jim Benepe, Scott Laycock, Stephen Leaney and Nick O'Hern join Baddeley four shots behind the leaders.
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