Dan Olsen, the leader after round two, posted a 5-under 67. He stands alone in second place at 14-under-par 202.
Englishman Brian Davis and Omar Uresti, who gained his tour card through this event last year, share third place at 12-under-par 204. Uresti, who has carded three straight rounds of 4-under 68, is the only player in the field with three rounds in the 60s.
Greg Owen (70), Rob Rashell (70) and Tjaart van der Walt (66) are tied for fifth place at minus-10.
The 169-player field are battling in this 108-hole event for top-30 honors, which would earn them PGA Tour cards for 2005. Players who finish out of the top-30, but in the top-80, will receive full exempt 2005 Nationwide Tour status, while the remaining players are non-exempt members on the 2005 Nationwide Tour.
Play for the six rounds is spread over the Stadium Course at PGA West and the Nicklaus Tournament Course.
Brehaut, who has partial PGA Tour status for 2005 after finishing 149th on the money list in 2004, took to the back nine at the Nicklaus course to start his third round. The 41-year-old got off to a hot start with birdies on 10 and 11. Brehaut picked up another birdie at the par-5 15th to move to minus-8.
The two-time winner on the Nationwide Tour came right back with an eagle on the par-4 16th. Brehaut, the medalist at this event in 2002, birdied 17 and 18 to head to the front nine after an opening nine of 6-under 29.
On the front side, Brehaut ran off three consecutive birdies from the par-3 third to jump to 15 under. Brehaut birdied the par-3 eighth before a par at the last capped a bogey-free round.
'It was just one of those days, everything went my way and when I did get into trouble, I came out smelling like a rose,' said Brehaut. 'I wasn't in very much trouble, though. I made a point not to let any of thoughts of 59 enter my head. I just said okay we are going to the next hole, let's birdie it.'
Dean Wilson and Phillip Price, a three-time winner on the European Tour, share eighth place at 9-under-par 207. Keoke Cotner, John Elliott and David McKenzie are one stroke further back at minus-8.
Sean O'Hair and PGA Tour veteran Esteban Toledo head a group of seven players at 7-under-par 209.
Scott Gump, the first-round leader and former PGA Tour player, continued to fall down the leaderboard. He posted a 4-over 76 to drop to even-par 216, where he shares 71st.
Bob Burns, the 2002 Disney Golf Classic winner, had a tough day sliding from a share of 16th to a tie for 102nd after a third-round 6-over 78.