Green fired a 4-under 67 to vault to second place. Kurt Barnes, who held the first-round lead, posted a 1-over 72. He stands alone in third place at 3-under-par 210.
Paul Gow (71) and Stuart Appleby (72) share fourth place at 2-under-par 211. Columbian Camilo Villegas is one stroke further back at minus-1 after a third-round 69.
Pampling began the day four strokes clear of the field, but his lead quickly began to fade. He stumbled to a bogey at the first and made it two straight when he bogeyed the par-3 second at The Australian Golf Club.
The Australian fell back to minus-5 after a bogey at the par-5 fifth. Pampling settled in from there as he ran off 11 consecutive pars.
Pampling posted the only birdie of his round at the par-4 17th. However, he gave that stroke back with a bogey at the last.
'The greens were hard and fast and my chipping was a bit off over the early holes,' Pampling said. 'If I can shoot even-par or maybe one or 2 under tomorrow I think I've got a great chance of winning.'
The left-handed Green got off to a quick start with birdies at the first and third to move to minus-2. He faltered to a double bogey at the fifth, but bounced right back with a birdie at six.
Green converted back-to-back birdies from the eighth to get to minus-3. He jumped to 5 under with an eagle at the par-5 14th. Green stumbled to a bogey on 16 before parring his final two holes to take second place.
American Bob Estes used a 1-under 70 to move to even-par 213. He is joined in a tie for seventh place by Australians Robert Allenby, Martin Doyle, Peter Lonard and Stephen Leaney.
Six more Australians - Nathan Green, Steven Conran, Brett Rumford, Paul Sheehan, Steven Bowditch and David McKenzie - share 12th at 1-over-par 214.