David Hearn climbed into second place at 11-under-par 202 after a 3-under 68. Stephen Woodard, Craig Scott and Cory Jones share third place at 9-under-par 204. Matt McQuillan and George Bradford are one stroke further back at minus-8.
Scott birdied the first for the second straight day, but stumbled to a double bogey at the fifth to fall back to minus-9. He came back to birdie the ninth before an eagle at the par-5 10th got him to 12 under.
Scott tripped to a bogey at the 11th, but regained that stroke with a birdie at the par-4 14th. He parred his final four holes at Derrick Golf and Winter Club to remain one shot clear of the field.
'I didn't play quite as well as the first two days, but I was able to get the most out of the round,' said Scott. 'Even after the double bogey, I was able to keep my emotions in check and not get down on myself.'
Hearn, who has a win and a runner-up finish in the last three weeks, struggled early with bogeys at the second and third. He came back with a birdie at the fourth and consecutive birdies from the ninth to get to minus-9.
He dropped another shot at the 12th, but collected birdies at the 13th, 16th and 18th to climb into second place.
'It's been good talking to the media every day for the past month,' Hearn joked. 'I'm sure this streak will end at some point, but I am playing with a lot of confidence right now. Steve has had a great week, and we should have a lot of people in our gallery tomorrow. Hopefully we will show them some good shots and then we'll see what happens.'
Jason Higton, who entered the round in second place, stumbled to a 2-over 73. He shares eighth place at 7-under-par 206 with Todd Tanner. Chris Locker, Paul Devenport, Ben Ferguson and Kent Fukushima are one stroke further back at minus-6.
Rob Johnson, the 2003 champion, stands tied for 15th at 5-under-par 208.