One shot in front going into Saturday at the Regions Tradition in Alabama, Green battled to a three-over 73.
The Victorian lefthander was unable to find any joy with the putter as he hit 15 of 18 greens in regulation and paid the price for a double bogey and two bogeys as he fell to a share of 10th place, five shots behind American leader Jerry Kelly (65).
Despite battling back issues earlier in the week, Kelly turned in his first unblemished card of the tournament in forging a one-shot lead at 15 under ahead of South Korea's Y.E. Yang.
Yang's countryman Charlie Wi (67) was a stroke back in a tie for third with New Zealand's Steven Alker (71).
Michael Wright was best of the other Australians, surging with a 66 to share 13th at nine under, with Greg Chalmers (70) a shot further back, while Rob Pampling (68) and Mark Hensby (68) were at five under, David Bransdon (72), Stuart Appleby (69) and Steve Allan (73) were four under and John Senden (75) 10 over.
After finishing with a flourish with three birdies over his final three holes at Greystone Golf & Country Club, the 58-year-old Kelly is in the pole position for his 14th Champions Tour victory.
"I'm happy that I found something that was working really well with the swing and the putter in the end," Kelly said. "It's just more of the same tomorrow, just got to keep the pedal down with these guys."
- with AAP
